94 Buick RoadMaster Estate Wagon LT 1 issues

[Bentwings]

I’m sure I posted some time ago but I couldn’t find it. Also did a search but couldn’t find that either.
So just to recap
94 Buick RoadMaster Estate Wagon LT 1
this Car only has 110k on it and is like a brand new car. A granny had it since new and it was like a daughter to her.

anyway the car has never seen a winter. No rust just minor weather stains.

So I get it and it runs fine for about 5k miles then it developed a miss across the board. Since I no longer have a place to work on cars I’m forced to “take it to the shop”. Well the shop tells me the trans is not shifting properly and needs rebuilding. I’m not buying this and go to 4 more shops all saying the same thing.
finally I run into a guy who is old school that “fixes” things rather than throw parts at it hoping to hit the one that works. He says the trans is fine.

Long story shorter.
new belts, air cleaner, oil change with Wix filter, fluids topped off. Suddenly the car stops running altogether. So new fuel pump and Wix fuel filter. Car runs but still has Miss. new Cats both sides, new O2 sensors (one was definitely bad)
checking the motor for leaks and we find the Opti Spark is saturated with oil. Seal behind it is bad. New Opti Spark and vacuum line, new water pump. New plug wires and plugs. EGR is not functioning. New EGR.
More scans. Motor is running very rich on left bank. O2 out if range so it is replaced again.

Now it runs rich on the right bank. But all sensors are in range and almost dead center of range.
Very thorough inspection of intake hoses. They all are nice and flexible, none oil soaked or brittle. All clamps centered and tightened....not excessively.

Now I might add that I specified to use all GM OEM parts. No MSD, no aftermarket hard parts. Mostly because of my experiences and others of my cruise groups. Even the OPTI was new old stock.

car still has a miss. Mpg has gone from 21-22 to 12-13. Also have run several tanks of non oxy premium through it. It still is solidly rich on the right bank.

i went and got the EEHACK and a brand new laptop just to run scans on this car. Even got a cool memory stick for USB port and connection to download to Apple IPad Air lol. Unfortunately misplaced during recent move.

however my scans show exactly the same as high dollar tool man scanner.

one thing that seems unusual in that I can’t reset the BLM while others say I should be able to do.

Last week my guy got a very expensive smoke tester. It showed no,leaks. I suggested he compression test the whole motor which means I get charged for plug R &R again.

I told him at this point I don’t care, just fix the car, what ever it takes, I need the car as my el Camino will be headed for winter storage shortly and the Buick will be my driver. It’s only been 6 months of messing around. He is getting tired of having the car around and I’m very frustrated.

i didn’t call him last week as I didn’t want to be a pest but he called me and said he had new OEM injectors coming Friday and would install them as soon as he could. He’s been very fair with charges and so I can’t complain there. Nobody else around will even look at the car now. They see me coming and they put the closed sign in the window.

Im looking for any help I can get. It may be a bad computer but the general feeling I get is that these hold up pretty well. There are at least 6 Other LT 1 in the cruise groups I hang out with and all are virtually trouble free. All have a log more miles on them.

byron

[steveo]

if one bank is rich it’s probably an injector or two. usually i would swap the lefts and rights to see if it follows.. but also the fuel pressure regulator could be leaking through its vac line? its hard to make an engine run rich. show us your eehack log maybe we’ll spot something

[Bentwings]

Thanks for the quick reply. My “guy” and I talked about this. Were I working on the car myself I’d certainly have tried swapping side for side. However since I’m paying him to do the work it’s more cost effective to just replace the injectors. The disadvantage is that if it works we won’t know which one or if all were faulty. He has rounded up new OEM injectors that he has either installed or will shortly. I’m going to stop by his shop later today and see how it’s going.

I’ve got four scans somewhere in this iPad but I’ll have to search them out. My memory stick got stuck in a box somewhere in the move and I haven’t found it yet.

I’ll post results later
Thanks

[Bentwings]

New injectors responded the same. Or no change which ever way you look at it. The compression test looked very good. Three cyl are running max rich one is only very rich. No motor problems as far as pistons rods and crank.

The interesting thing is that the left bank was originally rich. New O2 and Cat and it switched to the right bank. New O2 and Cat there made no difference. Been that way ever since.

I’m simply lost in the daylight over this car and it’s systems.

[Bentwings]

Update. We installed new injectors and new plugs again. Got. “0” change. The right bank is still dead rich. Tried new O2 wire pigtail. Nothing changed.

Finally we have decided to go with a new computer. It was supposed to be done Fri but I didn’t hear anything somhave to wait until Mon. If this doesn’t fix it I’m completely baffled.

I’m not sure just how the injectors work. Normally open or normally closed. Is it possible that the injector wires for the right bank are open or closed all the time, in other words an open or closed circuit That is supposed to open and close by the computer command?

[steveo]

there's constant power to the injectors. the power comes from two independant circuits from the fuse block (one for left and one for right). the ECM closes the ground to each injector to fire it. yours is a sequential injection system so they all fire individually depending on engine rotation.

i sincerely doubt replacing the ECM is going to do anything

to be completely frank with you, if you're replacing ECMs and injectors for a rich condition, your mechanic can't diagnose worth a crap. it barely takes any time to determine if the injectors are the cause of a fueling imbalance. you're just throwing money away at this point

how do you know it's running rich on that bank, anyway? and how do you know it's the entire bank?

still need to see that log...

[1project2many]

I feel there is more to this story. If no one wants to work on the car it's generally not the car's fault. From perfect to undiagnosably messed up in a short time is atypical. Good mechanic "actually fixes things" can't fix car??? Also uncommon. Belt and basic maintenance items repair bad trans? Huh??

I have 38 years' car experince and they way this is presented just doesn't work. I can't help but wonder about the good mechanic first. Sorry, but as a mechanic I've worked with too many guys that make convincing arguments that their incorrect diagnosis is right. When they don't fix the problem they are highly skilled at covering the fact with "getting closer" or "made a difference" or "that part was hiding the symptoms from the other broken part." And if good mechanic is actually good then I wonder about "like brand new" status of car.

Why is it rich? What are the symptoms of rich operation? Are you sure the symptom you're seeing is actually causing rich operation? How can O2 sensor be reporting okee-dokee if three injectors are "max rich?" And really, what is "max rich?" In my mind that indicates the injector is at 100% duty cycle... "always on." That's an easily diagnosable problem. The way the problems are reported requires interpretation, which makes an accurate diagnosis tough.

Oscilliscopes were once rare in the auto repair field but a shop without one today is not fully capable of diagnosing problems. The injector on and off time can be measured with an external tool to confirm that ECM is reporting correctly. Time for each injector can be recorded and compared. If all injectors are at similar times then injectors get checked for leaking or improper delivery rate. If injectors are open for same time, and are all delivering same amount of fuel, then it's not injector or fuel delivery problem. Stop chasing injectors and look for other issues. Good mechanic knows when to trust facts.

Spark plugs black? Wet? Dry? Oscilloscope on coil wire will show secondary pattern to determine whether or not plugs are being fired correctly, if voltage is going where it should, if cylinders are rich or lean. Good scope reader can tell if plug gaps are correct, if EGR is active, if cylinder compression is not correct. Good scope reader can see crossfire, failing wires, bridges in coil insulation. Good scope reader can do many amazing things.

How can O2 be "perfect" and engine be "max rich?" Oscilloscope on O2 sensor will show O2 voltage and signal pattern. Does voltage match ecm reported value? Does disconnecting injectors change reading on scope? How about reading from ECM? Good mechanic will be confirming data with trusted tool, not just accepting what's on computer screen.

Is the cam good? Is the vacuum signal strong and steady? A weak cam can produce good compression readings while failing to fill a cylinder fully. Vacuum gauge is one way to see this. Oscilliscope on MAP sensor signal can be even better. Oscilliscope on MAP can be read to see intake valve opening and closing, pressure waves "bounce" as valves are closed, throttle angle changes appear imediately, restricted exhaust shows up quickly. This Oscilliscope thing sounds more versatile all the time.

Why are we not suspecting an ecm? Because someone else's isn't broken? But you want this fixed so how can you rule anything out? ECM response to rich or lean O2 is critical part of feedback loop. High O2 signal voltage from rich engine should result in less fuel delivered. But O2 sensor value is fine: "all sensors are in range and almost dead center of range." So what is telling you engine is rich? BLM high = ecm adding fuel to correct lean problem. BLM low = ecm removing fuel. My feeble mind follows training from 1980's EFI classes. Misfire = fuel not reacting = excess O2 = lean O2 reading = ECM tries to add fuel. Engine is not rich! Engine is misfiring and ecm is responding as programmed. Did Good Mechanic discuss this with you?

I'm not invested in diagnosing this. The questions are for you, not for me. The way this is presented I do not believe there's much chance of successful diagnosis in an internet forum. There are too many subjective descriptions and there's too little actual data to work with. "I changed the injectors but they're still rich" is not the same as looking at a recording of injector on-time over time. "The O2 readings are perfect" does not present an opportunity to evaluate the O2 readings. It tells the reader "Don't bother looking here because you won't find anything."

Hopefully you and your "guy" will find an answer to this obviously frustrating problem.

[steveo]

injector pulsewidth (the output that your mechanic is questioning) is easily checked by comparing the duty cycles of all the injectors. if you suspect a bad output (in this case injectors) that output needs to be measured, then you verify if your inputs are sane, if they're sane, then and only then can the ECM is suspect. it would be really odd for an ecm to be in a failure state that erroneously delivers MORE pulses.

you don't need a scope to check that your injector outputs are good, a dwell meter will do too, does your mechanic have one of those?

a mechanic that has neither a scope and knows how to use it (new-school) or a dwell meter and knows how to use it (old-school) isn't really from any school, and probably needs to go back to school pronto.

the entire thing sounds like a waste of money

you could likely go buy a perfectly running LT1 car and swap the entire engine and wiring over with less time and money that have been put into this issue

but as a tuner and LT1 guy on a forum for tuners and dataloggers, again, i'd be willing to look at a driving log to see if all your inputs and outputs are sane, and give you theories based on that just as a brain exercise

[kur4o]

I really feel sorry for this guy. His mechanic is best at swapping good parts but not that good with diagnostics.

SInce there is a missing cylinder[ or random missing opti], that might be the reason it runs pig rich. Missing cylinder means unburnt oxygen in the exhaust, which leads the pcm to think there is lean condition and dumps fuel till the blms are maxed out.

The simple test to see what`s wrong is to force open loop and see how it drives and monitor 02s reading [Make sure the blm and int is showing 128]. DIsconnect the battery, at least for an 1/2 an hour, prior to tests to clear any out of range blms.


Post the eehack log to get more insights.


With eehack and the built in real time controls you can pinpoint any electrical and mechanical issues in less than hour, you`d better start diagnosing yourself if you want the car to get fixed.

[vilefly]

Sorry I'm late to the punch again.
Here's what has NOT been checked. The EGR valve and passages. A clogged catalyst.
1) EGR flow causes o2 sensors to read rich. Remember, the O2 sensor detects oxygen.....only. Nothing else. Displace oxygen with something else = rich reading from O2.
If the car is not driven long enough, carbon builds up in the egr passages from not getting hot enough. The right side just might be plugged + EGR valve hanging slightly open = left side false rich reading. Don't forget about a leaking EGR solenoid causing false activation of the egr valve. Unplug it and see if readings change.

2) A plugged catalyst. Makes it run rich (low oxygen). Run a backpressure test with a gauge. Can be a partial restriction, so a gauge reading is preferred. 1 psi per thousand rpm is acceptable for stock engines.

Get a noid light and put it on each injector connector (one at a time) while engine is running. Should answer the injector driver question.

Yes, I own a caprice wagon 1995 with an LT-1, go figure.

[steveo]

leaking fuel pressure regulator

[Bentwings]

I didn’t have instant email response tagged so I’m late getting back.
The guy has a top if the line Matco scanner/code reader. Plus the connector for OBD 1. It’s a wireless device.
You can see everything or focus on just one item with this device.

I’m a rank newbie to this level of diagnostics. I’ve used a dedicated scanner for my diesel truck and picked out the exact problem and fixed it. So that’s really the limit if my experience.
I also worked in the performance auto shop for a number of years. We did have an osciloscope but it was pretty primitive for the Era.

Anyway both his scanner and my dedicated laptop it’s it’s software show the same thing. I seem to be able to get a little further into the information in that I can select clear items. With one exception, I can’t clear the or reset the BLM box.
When you scan it clearly shows 3 cyl at max richness and one cyl very close. I thing for numbers it’s 160 and 150.

Looking at all other sensors the show generally mid range. You can see both O2 cycling. Both have been replaced. As have both Cats. A smoke test showed no leaks anywhere all the way to the front of the motor. I’ve not used one nor was I there when it was done.
I questioned whether there might be a cam and lifter problem. There doesn’t seem to be. However the real question is why did the event switch from the left bank to the right bank? Then it becomes non responsive to any changes. It has a new old stock OPTI Spark as well as new OEM wires and spark plugs. There is spark on all plugs.
There is low manifold vacuum. It measures in metric by the scanner and I recall about 10-11 inches by conversion. Also vacuum gage.
The car idles right on rpm but has a “putter” and an occasional “crack” from the right side exhaust. It feels like a dead ignition miss. The car does drive as long as it’s not loaded going up hill. Anything below about 55-60 it will drop out of OD or I have to manually down shift. It has the towing package gear which is 2.92 or there about. I can’t imagine the standard gear of 2.56 originally the car ran perfect. You could cruise at any speed and the trans. would drop out of converter lock and down shift appropriately for the speed. It was a joy and very easy car to go anywhere. Now it’s a PIA. I know these motors were designed to have torque at low speed and were very economical as well as decent performers in their day.

I too passing said it would have been easier and less expensive to simply replace the motor and wire harness with a known good one. It would have solved my issue of having a car that runs correctly. On the other hand it would be the ultimate “throw parts at it” solution. I should be like my dad might have said, “ I don’t care what you do, just fix the ..... thing” .
And indeed at this point I really don’t care. We have done everything “by the book” as well as by what I would think common sense. At every step we have weighed the option....will this fix it? Is this a reasonable option? Or are we just guessing?

I burns me that I’ve built some very high performance cars from the ground up that drove nicely. Started everyday got decent mpg, and were very reliable. My current car ‘77 el Camino has a 300/350 that starts at -5 to 95 every time gets as good mpg as the motor can and still passes ‘77 emissions.

This Buick is has to run under more emission requirements but probably 500 engineers designed and caused it to be built.
There is a lot to this thing besides just a motor with a lot of sensors. The wire harness is huge. We have cleaned and inspected many connectors. I don’t think this car was submerged or subjected to high pressure under hood washing. It was a lady’s car.

So I really appreciate any help or comments. You won’t hurt my feelings to call me what you like. I’m more interested in a solution to the problem. If you have to call me whatever to get the point across fine, if it fixes this problem.

[lionelhutz]

Can you easily cross connect the O2 sensors on that car? Some, you can do that and introduce a new issue while trying to fix a current one.

[Bentwings]

I don’t think this is possible. The car has a true dual exhaust with no interconnection between pipes. The O2 cables are relatively short. They are a good 3 feet or more apart. I’d have to check under the hood. Maybe the harness could be unwrapped. The shop is on vacation until Sept 2 . Sure wish I could simply go on vacation. Even living on my boat I can’t simply take off. Yet.

I suppose a test connector could be made. Were i able to have the car where I could work on it, I’d try and make some kind of connector. Somewhere I’ve got the under hood wiring lay out. I’ll did around on my computer and try and find it.

I looked up EGR faults and I don’t see any that I’ve experienced with this car. I know he did take it off and cleaned it and replaced the vacuum line. I’ll have to look up the construction of this one shortly.

Why or how this issue switched sides is still a question. It looks like a reversed wire harness but it may not be possible by design. It’s one of those things we go through in engineering when we design systems. It has a Japanese term but we always called it “idiot proofing”. It was a final step before releasing something to production. No matter how good it is, it can be defeated if by effort.

i had to think of the term. Polka-yoke. We called it poky yoke. It’s been 15 years since I retired so memory gets taxed.

There are many tests to be done on these systems. From a consumer or customer standpoint, what is the cost balance between removing or testing vs. R&R, besides the possibility of getting a bad “new” part.

[kur4o]

Some simple test to do.

1.Disconnect 02 wires and have a test drive.
2.Disconnect maf sensor and have a drive test


A log made with eehack will really ease the investigation of the problem.

Also there is no way to see that 3 cylinders are running pig rich and 1 is rich. It is bank related, not cylinder related.

It is known issue that when the blms are maxed at 160 they can`t be cleared, the only way to clear them is to disconnect the battery for 30 minutes.

If the blms are maxed it means that there is alot of free oxygen in the exhaust. It could be from cracked exhaust, leaking egr plugs, cracked piston or misfiring cylinder. If the engine smooths significantly when you disconnect the 02s it could be one of these.

[vilefly]

Intake manifold leak detected. Low vacuum 10-11" hg you say. It's time for the "bucket test" and the PCV test.

PCV TEST: Unplug the PCV valve from the valve cover - plug it off, and plug off the PCV vent in the other valve cover. Start engine. After 30 seconds, unplug a side, and look for positive pressure blowing out. If there is vacuum, the intake gaskets are leaking at the bottom of the intake ports, probably sucking up some oil also.

BUCKET TEST: With the engine running, pour water onto the intake manifold and see if it causes misfires and rough running. If there is a change, the vacuum leak is real, and should be either the injector O-rings or the intake gasket leaking on the top of the intake ports. Try to pinpoint with a squirt gun if you like.

One last thing. Did you ever use the eehack software to run a power balance test? You could also unplug injectors at will and check the RPM drop. Then tell us which cylinders test weaker than the rest.

[Bentwings]

Ok I did have a reply to Kur40 but I ccidentally hit the wrong key and deleted the whole thing.

We did do test drives with both O2 disconnected. No change.
Did not try the MAF test.

I did do the power balance test. The whole right bank is weaker. I don’t remember the number. It may be on one of the scans however.

I did ask him to do both leak tests you described. However I forgot to ask. The results. The smoke test is a pressurized test so it should have shown something. I wasn’t there to observe however. The smoke generator will fill the shop with smoke in a few seconds so it is pretty dense. I don’t know what is burned or heated but it billows white thick smoke everywhere.
However thebuniversal solvent ...water does a good job for leak tests too. Since there are new injectors with new o rings that can probably be ruled out. The water test should pin point better if there is a leak. I did suggest this a long time ago.

Here is the kicker though....why did it ( rich running) switch from one bank to the other.? this question comes up time and again but never gets answered.

I agree there is air getting in somewhere. Not too long ago I ran into a TSB that says you can legally disconnect the AIR system as long as it remains on the car even in Calif. provided the system still passes the emission tests. the fittings I think are SAE inverted flair. This came about because of their frequency of leaks that cause problems. Their value is questionable today as the EFI systems and motors are so much better. I haven’t had the car available long enough to do it for a while nor to just try it.

So I’m stuck until Sept 2 when they come back to work.

The weather is a bit cooler now so I may just get the car when they come back and do some of this myself right in the marina parking lot. I’m really tired of screwing around like this. It means someone needs to follow me home so I can move cars and it’s a 90 mile round trip.

Going to another shop is like this song by Phill Harris.
substitute. RoadMaster for “ boom da boom”
https://www.youtube.com/watch?v=h2H6qC23RPY&list=RDh2H6qC23RPY

Once again thanks for the tips and tricks.

[vilefly]

The switching from one side to another is not terribly relevant, believe it or not. I suspect the lower intake gasket at the bottom of the ports sucked up enough oil to plug up its leak due to gasket swelling. Then it went for the next weakest link, the other side, which is still present. But to me, a vacuum leak is still a vacuum leak, no matter which side it is. Sucks in oil, runs rich on that side. Will probably come and go, too. Oh, and new injector o-rings are something I never trust. They can be cut during installation by both skilled and unskilled workers alike. Chaos theory.

A smoke machine is nice, but is best used for EVAP system faults. Pressurization is nice, but there is always a valve open on the intake that will make you miss that particular intake port and give a false "ok" reading. Only useful in this case when the engine is running, and at that, inferior to the bucket test. Many vacuum leaks have escaped them, like the 4.8/5.3/6.0/6.2L engine family with the plastic intake manifolds. My original Bucket Test evolved from dealing with the dual carburetted honda prelude. Smoke machines weren't invented yet for automotive use. Started using it on the rest of the hondas after that, with their nightmare 3 barrel carbs and tons of vacuum lines.
The specific gravity, density, and inflammability are what make water the king of the tests. Also, anyone can do the bucket test. No skill required.

The possibility of the air injection check valves failing, and causing oxygen sensor error is a valid one, but it can be easily checked by plugging off the air inlet to each side, and rechecking. Wouldn't cause a severe lack of power, though.

[Bentwings]

Thanks all for the helpful information, I’ll have to wait until Tues to hear where it’s at and what was done. I’m afraid that the computer change didn’t fix it. I may just pick the car up and bring it to the shop I work part time at and park it out back. I can run a cord out there for power and I think we have enough air line for air. I have a new squirt bottle so I can do the exterior leak test described. I also can come up with something to do the PCV test. The car uses no oil and loses no fluids. If I can pin point a leak I can get the guy to pull the intake and do gaskets. His rates are reasonable so I can live with that.

I big issue is that my work is 50 miles from home so after a long day it’s hard to do personal stuff then drive another hour home. Makes a very long day.

I did find my laptop with EEHACK on it. I revisited the 4 scans that I saved. I’m going to go to the computer store today to figure out how to connect to the internet directly then I’ll be able to email scan directly. My iPad doesn’t like them.

More later.
Byron

[kur4o]

The lack of power suggest a massive air leak before the exhaust. If it was an exhaust leak, it will still run fine, fat rich. Probably 1 cylinder runing extremely lean[drawing unmetered air] with constant misfires, causing the PCM to dump huge amounts of fuel.

You can try reading the spark plugs for some more clues. Gaskets or cracks in the head, or intake manifold. Overheating?
Cylinder airleak test?
I will question any of the test you have already done.

[Bentwings]

I respect your questioning things. I do the same. At each step we have had discussions on what to do and why. I have searched for information and landed here. So I’m asking for help.

The plugs were clean and in good shape on the right bank for 100k miles on the car but the left side were heavy fluffy black but with less wear on the electrodes. My thought is there was an intermittent Miss on the left bank that gradually got worse. Long story short, the Opti Spark, plug wires and plugs were replaced after some discussion. After this it ran for a day or so but the miss returned. The O2 sensor on the left bank was out of spec so we replaced it but the miss remained.
We disconnected both exhaust pipes after the O2 ...near the mufflers essentially looking for bad Cats. The miss went away so we replaced the left Cat. The miss remained but on the scanner it showed the right bank being very rich now. This is where it swapped banks. So this is where is gets puzzling to me. Nothing seems to change it.

Now I had my own scanner with EEHACK. I think this is even better than the Matco or my sons SnapOn scanners. I’m a rank newbie with this but I was able to clear all the codes except the BLM. I didn’t know what this did so an internet search gave the name...block learn multiplier. Plus it’s function.

And now from the above post I learned how to clear it too. Im still concerned that the computer change will not fix this.
I’m not sure how it’s installed so I ask this question. I’m assuming the battery needs to be disconnected. If not what happens? Then can I disconnect it for 30 minutes and the BLM will reset or do I have to do this on my scanner.

A question here...will the BLM be reset automatically when the new computer is installed?

As you can see there is some knowledge or training missing here. I simply don’t know what to do.

I won’t have the shop answer until Tues but I’ll call him or stop in on my way to work Tues. morning.

again thanks for any and all help.
Byron

[myburb]

I don’t have cats and I don’t have lt1 but you have been working on this for awhile. Do I read it that when you took off both cats it was fine? If so could it be you had 2 bad cats with the left being worse than the right. When you replaced the left it fixed that side and now the right is the worse side?

[Bentwings]

Actually both Cats got replaced. I thought the same thing. It ran reasonably good a few miles but as soon as a load was present the problem came back and stayed there. If it still is running bad Tues. I think as kur4o notes it’s possible to have a big intake leak either internal or external or both. Therefore I think it best to just say screw the tests just put new intake gaskets in and make dog gone sure they don’t leak.

There doesn’t seem to be anything bad mechanically in the motor. It idles very smooth at the required rpm.it just has a miss. Actually not a miss fire but the right side has a putter or pop from the exhaust. Its irregular but periodic. I think It’s igniting fuel in the Cat due to it being very hot. I suppose from trying to burn raw fuel.

Once you get the motor over about 3500 rpm say in 2ng gear it starts pulling pretty well....considering. I’m guessing that it can better handle the rich mixture.

Byron

[1project2many]

You really want to follow a methodical test -> eliminate process to solve this. Simply replacing the intake gaskets is not the way to go imo.

I think the bucket test isn't a bad one but as someone that has helped more than one LT1 Vette owner after washing an engine, I would caution you not to douse the front of the engine if possible. Especially when the engine is warm.

I'm less inclined to believe the internal manifold leak will cause a driveability problem. Airflow into the crankcase is metered as it flows through the air intake prior to the throttle plates. The L31 vans were prone to manifold gasket failures yet the engines usually ran well. We would see coolant loss or oil consumption but the engine would not appear to run badly. I would plug the fresh air connection to one valve cover and install a vacuum gauge in place of the PCV at the other. If the gauge showed vacuum with the engine running then the gasket was slated for replacement.

Don't get trapped by the BLM. You can trick the pcm into thinking the engine is too rich by sending a "too high" O2 voltage signal. .7V to .9V is enough to cause the pcm to flag the O2 as rich. A very simple way as the mechanic is to become an active part of the O2 signal circuit. One hand to battery + and one hand to a bare length of wire installed in the O2 signal circuit is enough to raise voltage so the pcm responds. And the pcm should respond! Once BLM values go to a reasonable level you can disconnect the sensors and force open loop. The ecm will deliver fuel at the commanded AFR without correction. And you will be able to tell just how the engine is running without the pcm trying to cover it.


I big issue is that my work is 50 miles from home so after a long day it’s hard to do personal stuff then drive another hour home. Makes a very long day.

I agree. I think you should move the vehicle to a location that helps you get the testing done that will resolve this.

[Bentwings]

Right from the start we have tried to be systematic and logical as we searched for the issue. Interesting is that there was never a check engine light. It does work however.

I think in EEHACK you can force the ECM to run open loop only. It’s something I have not tried. I think you would also have to trigger the BLM as you noted. I don’t know however. It’s uncharted sea for me.

If things don’t go right then I’ll have to insist he at least do the PCV test you describe. I won’t douse the front of the motor. I’ve already been cautioned about that. Don’t do under-car car washes either. I think the squirt bottle will work for the topside. That’s easy enough to do.

I did find the memory stick with the 4 early scans and the iPad adaptor. Now I have to see how the download works. I did it once before but iPad didn’t like it.

[Bentwings]

I didn’t have a good feeling about the computer. It didn’t help a bit.

I visited the shop today and we chatted for an hour about where to go from here. We talked about the intake possibly having a leak either from the outside or from the inside or both. Then what to do about it. He can spend time testing it to determine then what? If it shows a leak do an R&R and replace gaskets. Glue it up good with sensor compatible sealers. It boils down to cost. He flat asked me “how do I charge for this? “. I said that this point I’m so deep I’m drowning, deeper and I’m still drowning. I said I would charge flat rate and something for test time. I’d test it as much as possible for my information but the end result is that it needs to be removed and new gaskets whether or not the tests show anything just to eliminate a question. We have done so much of this already that one more item will just add to the list. It’s the front cyl and the back two on the right bank.

Additionally there could be a cracked manifold or cracked head? Or both? However the switching sides enters here again.
The motor idles smooth even though it’s dead rich on three cyl. It just putters out the right side tail pipe.

He is going to donanothe check of the exhaust manifold. I suggested he use his bore scope to possibly get a closer and better look from above and from below. Possibly simply replace exhaust gaskets if there are any.

The other question is the knock sensors. But would they create this? Then would they not produce a code? Again there are no codes showing.

We also talked about the possibility of sticking or broken lifters. But wouldn’t this produce some noise and rough running?
I had flat cams before but they lacked power and made at least a little unusual noise.

At this point I’m really lost on what to do. Something tells me the intake gaskets aren’t going to fix it either.

Any help will be greatly appreciated
Byron

[vilefly]

Screw the exhaust manifolds, knock sensors, and lifters. Waste of time. A cracked head would overheat or drink coolant or put exhaust gasses in the cooling system. There is a tester for that. Coolant can skew the o2 readings rich, but you can smell the burning antifreeze most of the time. A cracked exhaust manifold would affect 4 cylinders, not 3. A collapsed lifter ticks...period. The intake manifold tests shouldn't take more than half an hour to do a thorough job.

Sounds like you tend to make 3 steps forward instead of one. Best to treat it like a timeline. Each choice leads to a different direction, so don't take more than one at a time. We still don't know the condition of the intake gaskets. Wait for the answer to that first. Quit wasting money ya young impatient whippersnapper.

The only one time I have had an exhaust manifold be the cause was when it had a piece of catalyst honeycomb stuck up in it, and that was because the guy was racing it.

Another strange condition that affects things is heavy carbon deposits on the valves from burning oil. Deposits so bad, it was blocking the injector spray from getting directly past the valve. Fluffy thumb-sized restrictions, I mean. On other vehicles, enough carbon to hold the valves slightly open or prevent them from sealing properly. Revealed by a cylinder leakage tester and a running compression test (with engine running). Would also cause low vacuum. Looking down the injector holes in the manifold would show if it was the case or not, but I trust my eyes least of all. Can't see a compression leak, you know.

The other strange condition I ran into was after someone overheated the hell out of an old small block chevy. Got it so hot, the valve springs weakened enough to not seal the valves well enough to run worth a damn. I had figured it needed a valve job, but was slightly wrong, until the weak springs allowed the valves to get burnt.

This is why we do it one step at a time. Weird stuff.
By the way, your old computer will sell just fine on ebay.

[kur4o]

The next step is to upload some logs, and get familiar with eehack control window, so you can do some real troublshooting of the car.
From here any suggestion without a log will be shooting in the dark. I am sure it is something as simple as being overlooked.

Leaking coolant can foul the 02s heavily, so the blms can max out. I have experienced it once. But you will get smoke from the exhaust too.

You can do the water cleaning trick. Warm the engine, disconnect maf and air cleaner. Increase rpm to 2500-3000 and start spraying a fine mist of warm water in the throttle body, so it can enter the engine. You can vary the rpm and the mist. Half to one pint of water will be enough for the first cleaning.

[daveosx]

I love these Engines

A couple of really simple things to check.
1. One bank rich in 94-95 the EGR gas flow was pulled off from a port on the exhaust manifold these crack and leek Air into the exhaust manifold causing O2 to read lean and BLM to go up.
If the little tube is cracked it will make that side rich.
If you have the cast iron manifolds you may also have a crack there.
Any exhaust leak from the head down to the sensor will make it rich on that side.
2. Correct PCV valve for old engines I use a 774 standard it works and does not lean out on old rings.
3. The 94 throttle body had a tendency to clog where the PCV goes into the top of the throttle plate right under the badge plate on the throttle body without PCV you will foul the O2 sensors.
4. Oil fouling often people think that low miles old cars mean that they are in better shape, this can be problematic if the owner actually let the car sit for extended periods or worse the car was only driven 3 miles a day.
These engines are designed to run with the oil in the block at or above 220 F if the oil does not get to 183 F then it will be soaked with ethanol from the gas letting the car sit the low tension rings get damaged.
If you get oil on the plugs then the sensors will foul and it will go full rich. I had valve guide seals go bad after an overheat that did this to one of mine. I used a spark plug extension drilled out to move the O2 sensors out of the exhaust flow to allow normal driving until I overhauled it.
Heres a link to some one else describing how to use them.
https://www.evolutionm.net/forums/evo-how-requests-questions-tips/114931-how-install-spark-plug-anti-foulers-remove-ses-cel-light.html
5. Persistent miss, I have used a lot of these coils and modules for all kinds of builds a couple of common things on the coil that will cause a miss is that the epoxy fails look for white powdery residue around the coil body and bracket. If found replace the coil and coil wire. Another area that the OPTI had issues with is the short wire harness between the Opti and the engine harness on the passenger side behind the water pump.
6. To localize the miss pull one injector lead off at a time and find the missing cylinder. If none change then look at the ignition closely the wires that are clipped to the block behind the exhaust manifolds may be sorting out.Take off the serp belt and use a test light to puncture each plug wire and watch for miss. If no miss found pull the valve covers off and look at the rockers as you rotate the crank the early roller lifters where common to fail and wipe the lobe of the cam.




One of my project builds is another LT1 engine
I am going to use a set of CompE Speedmaster heads on one I have the heads already On these the oil return passage can be plugged to open the reverse cooling port to fit Gen1 heads on the GenII block.
I love really old school tech fusion so the plan is to use the LT1 lower end with TRW1157 flat tops and 3.75 stroker crank after market main caps and a girdle.
With the new build looking for monster torque.

I have one of these motors that had a LT4 cam and wildly ported heads 280cc intake runners with Orange springs and a lifter REV kit It turned 9000 Rpm.
Stock coil won't even pull 6K The OPTI pickup works great all the way high as you want to go MSD cap and rotor held up pretty good. I used my own Ignition controller and CATS tuner to tune the ECM OBDI.
The old screamer will be getting new springs pistons and a overhaul looking to put 4 small turbos on it.

FYI the stock injectors are like 26lbs so if you are tuning it you could have bought a really cheap set of 44lbs EV1 style micro drilled injectors for less than 80USD.

[Terminal_Crazy]

Stock coil won't even pull 6K The OPTI pickup works great all the way high as you want to go MSD cap and rotor held up pretty good.

What would you advise to use for a coil upgrade that won’t melt the opti ?

Thanks
Mitch

[Bentwings]

Vilefly, I’ll try and follow your suggestions.

Since I got the car I have used it to go to work. It’s about 45 miles depending on route each way. 95% highway cruising. Traffic often goes 75-80 for about 20 miles. Then about 55-60 the rest of the way. There are a couple miles at the start and end of city driving so. There is a long grade about 6-7 miles. I don’t know the elevation but traffic still goes 75+ up it. The car could do this easy and I was a left lane cruiser everyday. So it got lots of fast lane use for the first 6k miles. Then the issues started. It never over heated the gage stayed dead center, it never burn or lost oil, never used coolant. Basically a perfect highway cruiser. I was very happy with it.
Then it developed a miss, slight but it caused a lack of power and the converter and trans acted up. Dropping out of lock up then out of OD. I thought the trans was the issue. I went to 5 well known shops and all wanted expensive trans repairs. However I was suspicious since I was driving the car everyday and had begun knowing it. So I asked if this would definitely fix the issue. They all said the trans was the issue but said the motor was fine. I wasn’t buying this besides there was no guarantee they problem would be fixed.

So I looked for good shops with OBD 1 scanners. Few had them. Some wanted to charge me to upgrade their stuff. Forget it. I finally found the shop I’m at. He also does trans. He had it for a day and really flogged it. He said the trans was perfect but there were issues with the motor.
Long story short, step by step issues were addressed before a really complete scan of the motor operating was done. The Opti Spark was full of oil and caused ignition issues. Bad oil seal. It was replaced with new old stock unit. Along with wires and plugs.
And so on, everything was done with discussion of why this or that needed fixing. Bottom line is today there is nothing showing on his scans and mine using EEHACK except for low manifold vac.

There is no real anti freeze smell, no oil smoke, just a random puttering in the right exhaust. Scans show the front cyl and the back two on the right bank dead rich. BLM maxed out. The plugs on the right bank are all fluffy black but not packed. We have replaced them three times already.

So we spent an hour discussing where to go. I have to give him credit for being patient with me and not over charging me. I know he needs to make a living so his time is of value. I have no choice but have someone do my work as I simply do not have a place to work on cars.

I’m at a loss now so depending on others who really know this system. I’m trying to learn too. In some cases tests simply need to not be done and just fix a suspected problem. Certainly not the best way but economics enter too. I hate this but it’s less Expensive to just do it and look at the cause afterward. Certainly a poor way of doing things.

If you scan this thing with a parts store scanner it will show nothing wrong. It takes something that scans deeper so enter the SnapOn or Matco or EEHACK. And now we see an issue. Every attempt has failed to fix this. Certainly some were unnecessary. I know this and have to accept this.

We now are at perhaps what should have been done earlier position. Were it a carb the manifold gaskets would have been replaced early on....I think. I would have done this myself based on carb experience.

So maybe by late tomorrow I’ll know what happens. Even this I still have misgivings. I can’t imagine real hard parts failing this way. The switching side for side of the problem keeps coming up. But now with the intake issue “fixed” it may point some other direction.

I don’t like making long post but I like to present the issue as complete as possible.

I did try to post my scans but I simply can’t from my iPad and down here on the boat our WIFI is very unstable. I’ll take my laptop up to my sons this weekend and see if I can work something out.

I know y’all are trying to help out so thanks again. I’m listening ...reading.

Byron







[vilefly]

I would like to state for the record that I said test the manifold, and not replace anything yet. The small block chevy, prior to the CPI vortec motors, seldom had intake manifold gasket failures when the OEM gaskets were used. When they eliminated the center bolts for the manifold, things began to fail. There is a slight possibility that the gasket rotted out from underneath the metal edges of the ports, but it doesn't happen often. Just make sure the rest of the manifold ports and gaskets are sealing, too.

Hopefully, there is not a constant hissing sound from the brake booster when you hold down the brake. A leaking brake booster can skew things, too.

[Bentwings]

I have not checked the brake booster but I’ll do that. The brakes are very good on this big car. Very light pedal.
The motor doesn’t make much noise even with the hood open. I have heard no “hissy” sounds at all. I’ll have to ask as I don’t remember. Early on the EGR was looked at and serviced if not replaced. There was a problem with the vacuum line or something. I’ll ask him.

I missed calling him Fri so I called today....no done, finish tomorrow. He is really busy I know that so I’m trying to be patient. The weather is turning early I think this year. Miserably cold and driving cold rain and wind today. Got soaked then had to go back out and snap down the rear canvas on the boat.

I still have an uneasy feeling thatbthis gasket job isn’t going to fix it. I’ll be totally lost. I asked him to take a look at the valve action, possibly a flat cam. Also look down the ports of use the bore scope at the intake valves and see if they may be really carboned up. I’ve seen some really bad ones that only caused a little loss of power.

So more later.

Byron

[Bentwings]

Long story short I wasn’t able to contact him until this morning.
The intake is still on and he hasn’t don’t anything productive. I should be fuming by now maybe a melt down is in order. However I need this car, shortly winter is coming and I don’t want the el Camino in the salt bath winter, besides its nearly as bad as my truck for traction.

So he wants to do more external stuff. What the H ..... more can be done? I’m going to go out there shortly it’s a long drive but I can go to the shop where I work just down the road and make Something for my boat I need the time on the boat more than chasing this car.

I’m going to ask to remove the valve covers and check over the valve train as close as possible. Valve seals are not real easy to see but possibly they can be seen better with his fancy bore scope. If a doc. can see inside my a.... surely a snap on scope can get close to the valve springs and seals. Next watch and observe the valve action. Flat cam? Don’t think so but failed lifters maybe. The ‘scope may be able to be poked in the casting openings to look over the top of the lifters.
Next I was out with my dog and thought maybe by pulling the injectors it would be possible to look down this hole right at the valve. They maybe massively carboned up. It only had 100k miles when I got it so in 25 years so that’s only 4 k a year.
I want to revisit the EGR from the note above. I don’t think the knock sensors have been looked at or were ok according to the scans. Also I want to do the BLM reset by disconnecting the battery. There was another test that was quicker. I’ll request we try that too.

Question here, with EEHACK, the BLM can’t be reset. So by disconnecting the battery does this enable a reset or is it automatically reset? Do I need to disconnect my OBD 1 cord during this process?

I also want to do another scan with EEHACK on my lap top. Speaking of which I need to be able to send these by email. I’ll swing by the Apple Store and see why I can’t do this.

Digressing a moment, I was in the hospital ICU after a fall in the snow. I had blood on the brain. It was a very hard fall, face plant. The doc said I know what happened but there should not have been a couple symptoms I noted during the operation. I’m going to do an angiogram to look further. Normally you would be clear to recover but I don’t like these things and I need to do more work. Then asked for the usual signature. He went ahead then showed me what he found and repaired. It was so small he needed a microscope on the probe to see it. But this is what is lacking in auto repair shops today.

That’s not many trips to the grocery store and it was never driven in the winter. So these are tests that I dreamed up in the last hour and a half with my dog.

Now it’s not a lot of RR but a lot of screwing around testing “is it this or that” then find the intake is still questionable. Taking the intake off is part of a valve job so it's already partway there, if looking in the ports and a problem is seen you can continue with productive work. You should be able to identify leaking gaskets external or internal probably both. I’d say do this. Then if it doesn’t fix it then were I the mech I’d have to tell the customer that “I give up, we have done everything, tried not to throw parts or work at it, but the problem persists. I simply do not have the extra knowledge to fix this, let me help you find someone else.” I would respect this instead of ongoing, “ didn’t get to it today, have it done tomorrow, multiple times”.

I m searching the local area for another shop too. Frankly most are rip off places, there are few really honest places. Most will not listen to what has been done nor thoroughly scan and check things. I found this with the trans. shops I originally visited. I also asked my streetrod friends where they go and why. Many no longer do a lot of work on their cars as their health simply does not permit this labor.

I want to revisit about everything you guys have noted above. Either myself or with external help.

I just looked at a new Edelbrock ProFlo 4. It’s been a very good system with good tech support. It would be a stretch to install this, just dreaming.

Thanks everyone for the help. I hope this thing gets fixed soon.

Byron

[bradyzq]

Did I miss the part where you did compression and leakdown tests?

If so, what were the results?

Also, using eehack or the shop's scanner, what are the injector open times on each bank?

[vilefly]

I think he's too busy dodging invisible bats and manta rays all swooping and diving about the roadmaster. Don't worry. We will start seeing them soon enough. What he is going through is why I had to become a mechanic.....so I wouldn't have to depend upon fools with tools.

[steveo]

i just decided in general not to let other people touch my shit if i can avoid it. house, bikes, cars, electronics, construction, anything. these days anyone can learn anything if they have a clue, and the more fundamental knowledge you get, the more you can do with less effort. there are very few exceptions that i'll make

people that throw a car at a mechanic and just let them go wild deserve what they get. if i hired a professional mechanic and they misdiagnosed a part replacement, i would demand that the old part was reinstalled and the bill doesn't reflect that unprofessional, uninformed, unskilled mistaken diagnosis.

i work in marine mechanical where most shops around here say diagnosis is approx a one hour charge no matter what the issue. if the issue is complex we use oscilloscopes with a multitude of probes, we break out handheld FLIR cameras, throw borescopes in holes, and then apply the knowledge of everyone in the shop in figuring out what's actually wrong, and when we are incorrect we go 'ohh cool! we learned something' and our client (not customer) is not responsible.

[spfautsch]

I wouldn't have thought it possible, but I just gained a newfound level of respect for you steveo. Other than one (out of four) alignment job(s) and having tires mounted I've allowed no-one to touch my stuff for going on 15 years now for the exact same reason(s). The semi-annual safety inspection was something of a show until I found a local mechanic who understood I did all my own wrench work and wasn't amused to hear a "you need a new PCM" diagnoses.

Regardless, I fear common sense and altruism are continuing to die a slow death. I knew this process had become irreversible when I found out that GM dealers were charging customers 4 to 6 shop hours to replace headlamp bulbs on their lambda body vehicles.

[steveo]

Regardless, I fear common sense and altruism are continuing to die a slow death. I knew this process had become irreversible when I found out that GM dealers were charging customers 4 to 6 shop hours to replace headlamp bulbs on their lambda body vehicles.

that's so awesome, in four hours i could change every light bulb in every vehicle i own including dashboard, and i bet you could too

they need to keep their doors open somehow, right?

[Bentwings]

Hopefully today will be the day.
I spent another hour on the phone going over all that has been done. Sorry to say but I have to take some responsibility for replacing suspect parts. Since I have to pay him for time, most instances it’s simply quicker to replace a part rather than test it or put in a different position. Even adding the cost of parts. In each case we have weighed this. This car/motor has been completely unresponsive to virtually every thing done to it. All parts replaced have been OEM no aftermarket stuff. My feeling is that this car is bone stock, millions of these motors have been produced and there are lots still on the road with little maintenance. Plus many have been very successfully hotrodded.

So in the last week everything has been reviewed, even a brand new scanner was used. Additionally the vac brake booster line was inspected for leaks but it is like new, the EGR is function as it is supposed to, each vac line has been looked at, the Opti was looked at and there is spark every time and firing order is correct. Plug wires are new and not contacting anything to cause shorting. Once again one side of the exhaust was disconnected then the other then both. Both cats are new. O2 sensors were switched to satisfy both are working correctly. The intake system was reviewed and is in excellent condition. MAF sensor is ok. We even put in another new air filter.

Then the valve covers were removed and the upper valve train checked for broken or damaged springs, everything is operating good with no noise and the valve lift seems even. Then the injectors were removed again and a bore scope was used to check for carbon build up in the ports or on the valves or anything else causing issues. The idle speed is steady at the spec rpm. The motor itself does not miss, it is just rich causing the fuel ti ignite in the cat. It’s not regular and only on one side, right.

The car does not burn oil or lose coolant. It’s dry underneath.

He was about to R&R the intake when I called Wed. Frankly, I have an uneasy feeling this is not going to help. The comment above about replacing the entire EFI unit with a known good one intrigues me. I passingly mentioned this earlier.

One question that remains on my mine is the possibility of a bad wire or wires somewhere in the system. Everything is connectorized to creat a new word so it is not exactly easy to single out a wire. I suppose I could go to the you pull and see if I could find an identical wire harness. Possibly install it and hopefully the problem would go away. With that harness it would be possible to cut and splice wires in hopes of finding the problem. If the intake R&R fails to fix the problem I may just take the car to my sons shop where I can work on it. It’s over 60 miles each way so the drive will not be fun after a day or two. But cost wise it may be my only alternative. The question is....how interchangeable are wire harnesses. For example Would a 94 Camaro or Firebird harness be acceptable? How about a 94 Caprice sedan or car? Actually if the harness swap worked I’d be more inclined to leave it alone an just use it.

If I take the car back I’ll rescan it with my EEHACK. I have four early scans but I can’t send them off this IPad. The lap top does work on the internet but I need a reliable WIFI connection which I don’t have here on the marina.

Regarding local marine mechanics. They have been totally unreliable and very expensive. I do all of my boat repairs....it’s like living in a garage. It may not be easy but at least I don’t have to go anywhere to work on it. Boats are another world altogether. The wiring can be unbelievable.

Once again I really appreciate the help
Byron

[LeMarky Dissod]

When you changed the injectors, did the orings get changed? Those pieces of rubber are now old enough to drink, but they are often overlooked.

When you changed the plugs, did you also change the wires? If you did, were the plug wires' heatshields put back on properly? I for one think all 8 of them should have heatshields.

When you changed the Opti-Spark, did you also change the Opti-snorkel? If the Vent & Vacuum Harness is bad, no Opti-Spark connected to it will work well for very long. Then after resting a while, it'll work again for a while until it fills with ozone again, and so on.

If your inlet manifold is removed, after it gets cleaned, but BEFORE it is reinstalled, soak it again, then use compressed air on the idle air passages that run from the IAC passage under the two main throttle holes.
Or just force whatever cleaning solution is being used thru the IAC hole until it sprays out the other eight ends.

The Idle Air Controller feeds the smaller hole underneath the two larger main holes, and follow paths parallel to the main runners underneath them, emptying into each respective cylinder's runner near the very end of their respective paths.

So far, I have not seen a single LT1 inlet manifold that has had its idlespider properly cleaned during a socalled cleaning. I've also never seen a single pic of any LT1 inlet manifold that clearly shows the ends of the idle air paths.

Probably not a bad idea to clean out the EGR and PCV passages too.

Hope this helps.

[Bentwings]

Yes, new orings were installed.
Yes new plugs and wires installed, heat shields reinstalled and positioned not to be close to boots or wires.
Yes, new Opti installed, new vac tube....old one was oil soaked. So was old Opti. New oil seal installed.

Thanks for the manifold tip. I didn’t know of these passages. I’ve not seen anyone else mention them. I passed this info onto the shop.

The shop closed early Fri so I missed then. I should hear Mon or Tues.

[vilefly]

Yep, we charge 1 hr for diagnosis, and we make sure we are correct, or no charge for the erroneous part installed. Don't know how other shops get away with it and stay in business. If we have to chase down a fault in the wiring harness, it is a separate flat rate charge not to exceed 1hr without notifying the customer. Seldom takes more than an hour anyways. Now, if the customer tells us what part to replace, we do not guarantee results....ever. If I do not concur with a customer's diagnosis, I let them know it before work proceeds. I just don't like wasting time arguing with certain types of people that annoy everyone around them in their quest for vanity.

[kur4o]

I bet you have a cracked exhaust manifold. Much cheaper to change than trying to diagnose.
Don`t go to the daunted mistery alient wire strategy. It is pure waste of time and effort.
The only time I have seen topped blms were when there is alot of fresh air in the exhaust or there is heavy gasket failure with coolant in the cylinders leading to flase readings..

[Bentwings]

I really appreciate all the advise. The info on the idle air passages is of particular note. Somewhere I asked how the and where the idle air passage was. I have never seen a picture of the right side of the intake. I’ve been blown off when questioning the idle air function and how it evenly distributes the air. When the idle air goes through the metered controller then is directed to each port in the proper amount is quite amazing. The usual comment is that if the scanner says the idle air is within limits,it’s ok. But above indicates that it’s possible, maybe likely that these manifold passages are blocked or restricted. I sure would like to see the bare manifold. We’re i doing the work it would be boiled clean or otherwise carefully cleaned. Transmission shops have great cleaning machines. Our boiling tank was banned by the EPA many years ago.

Since I’ve moved to the boat and marina I simply can not do my own work on cars. I do service my boat myself. To side track a moment, I’ve installed a new AC unit, repaired the anchor winch, replaced the sliding cabin door tracks and rollers and added a support roller, repaired nav lights, built a step for the transom exit doorway, built a swim platform riser so it’s flush with the dock, added new dock lines including splicing the loops., cleaned and repaired the water system, built a new cabin table, changed oil and filters on both motors and vee drive transmissions, pumped the bottom of the fuel tank free of water, and winterized the entire boat last year. This year I won’t have to as I’m living on it, currently I’m installing a winter heater. So I’m not opposed to getting my hands dirty. My boat is my shop now.

We have looked for a cracked exhaust manifold. We looked from the top and from underneath on the hoist for this early on. I would think you could hear it, as quiet as the motor runs. The pipe that holds the O2 sensor has been replaced on both sides. We have removed them twice looking for leaks but they are clean and tight.

Vilefly, I’d gladly pay you to look at this car. As big as this town is and as many hotrodders there are, there really are not many really good shops that can get right into the nitty gritty of a problem like this. I’ve been blown off so many times that I just don’t even care to deal with them. I’m not the easiest customer to deal with but I do require straight up work. I will not be part of a “shop project car” that sits for months on end with nothing done. I require a finish date. But when the work is completed and the result is not fixed then we need discussion about where to proceed. He has been very good about this and not charged for a lot of testing and diagnostics.

We are going to revisit the exhaust manifolds if the intake cleaning does not fix it. A good many connectors will be separated so possibly something might show up there.

[vilefly]

For now, it's just me and one other guy at the shop, and we are trying to keep up with demand. Basically, it's full-on resurrection season in the fall season, and ......it's fall. My boss is the other set of brains for the shop, and he has been away from the shop trying to fix sell his deceased father's house. Not sure if he'll ever get it done, being a perfectionist and all. I have lots of people dropping off cars as if we have a layaway plan or something. I get it done, they take forever to pay for it or pick it up. I could take a look at it, but I cannot dedicate myself to it completely. I tend to put these kind of "somebody else's diagnostic failure" cars in a rotation pattern in between the straight up "turnkey" vehicles which pay the bills. I try to get the straight jobs done in a decent amount of time, then I allow some diagnostic time for the mystery vehicle in between jobs. So, promising a solution to a mystery problem in a certain scheduled time and date won't happen. It contains too many variables at this time.

We are located in south kansas city, mo. Not sure if you are hundreds of miles away or not.

Here's one thing I never heard throughout this discussion. Has the computer's powers and grounds been checked out electrically, under load conditions, at the computer connector? Does this guy have access to schematics, and know how to test for these things?

As to the changing of the entire harness to fix one wire.....the answer is NO. Don't do it. Not worth the new problems you will introduce......like the other hole in your wallet.

Granted, you still claim to have a low vacuum reading, which still indicates a mechanical problem, but I am starting to wonder about the mechanic in question.

[Bentwings]

Today I stopped by the shop to see progress. He had the manifold off and soaking in cleaner. We looked at the gaskets. These are thin steel with something between. Very smooth. There was a slight sign of maybe leaking on two adjcent ports. Just a slight discoloration. Otherwise they looked ok. You could see the intake surface machine pattern but not really feel it. The chins wall sealer simply fell off with some leakage ther. Otherwise the motor looked pretty clean inside. The head ports looked ok even with flashlight shining not much carbon. We looked at the throttle body where the IAC is and you could see the entrance to what must be the IAC spider. They are not very big but there was some carbon build up. He said he would clean that up on assembly.

I sure hope this fixes it .....but I have my doubts.

So maybe that’s the issue. Hopefully he will have it done Monday. He is very busy with winters prep things on cars.

[vilefly]

Hook up a vacuum gauge when you are done to see if it returned to normal (18-20" of Hg).

Had a 94 firebird come in with the opposite symptom yours had. It kept adjusting lean in closed loop on one side until it started missing out, because the BAD o2 sensor stayed stuck at .56V, and it RELENTLESSLY believed the o2 sensor without setting any code for it. Replaced the sensor, and cured it. I seriously wonder about your O2 sensor wiring, but we still had a bad vacuum reading, which trumps the electrical with a physical problem. A shorted-to-ground O2 sensor harness may be your other problem. There should be a .45V reference sent from the computer to the O2 sensor's output signal. Unplug the O2 sensor and look for that exact voltage +/- .05V. If it is out of range, begin the hunt for a bad ground or short to ground or open circuit.

The latest beta version of EEHACK 4.8.2 lets you reset the fuel trims, which is a great tool for finding the truth about O2 sensors. Reset, and see if it smoothes out.

[vilefly]

Reviewing post #12......."There is low manifold vacuum. It measures in metric by the scanner and I recall about 10-11 inches by conversion. Also vacuum gage."

I am wondering if this was a MAP sensor reading instead of a vacuum gauge reading, for they are opposites. Map sensor reading = Barometric pressure - vacuum reading. So if I assume this has been posted wrong...... baro pressure (29.89) - 10" MAP = 19.89" Hg vacuum reading. Which would be a normal vacuum reading. 10-8" Hg of MAP pressure is normal.

The statement "also vacuum gauge" might not hold any weight. This is disturbing. I suggest you clarify.

[Bentwings]

Ok so we have the right bank at max rich ness so the car barely runs. Actually runs better at speed.
Also very low manifold vacuum. So obviously a leak somewhere causing the computer to try and compensate. However it’s already maxes out on the right bank. The O2 reads only unturned oxygen. It is showin lots of unturned oxygen, so doing it’s job.
More air is getting into the motor and exhaust system than can be burned or combined in combustion.
Where is this coming from? Intake air tubes are in excellent condition. No leaks around any joints ,confirmed with fluid tests . Injectors and orings have been replaced. With no effect. EGR is operating, Pvc is operating. No leaks here. Brake vacuum line is good. Exhaust manifolds seem ok, no broken bolts, joints have been cleaned .That leaves only the intake
Gaskets. The manifold has been removed and gaskets are being installed.

I hope this fixes the problem. I only had a brief look at the gaskets but there was no indication of blow out or “squeeze out as some indicated. The IDLE AIR spider did hav some carbon in it that has been cleaned out.

Keep in mind that this car probably was not driven much of its life. Mostly short trips. So the chance for carbon in various places is possible. The cyl bores and intake ports were previously checked as ok.

Well in a day or two I should get the car back and we”ll see if it is finally fixed.

I appreciate the help and it’s caused me to investigate issues myself. IE educate me. I’ve learned a lot and if this fixes the car I’ll try and do weekly scans with my computer just to see howThe car is working.

A side note, recent medical issue has left me with double vision up close so typing is not perfect.

[vilefly]

I was only questioning whether or not an external vacuum gauge agreed with the MAP sensor readings or not. The formula (MAP reading + Vacuum reading = Barometric pressure) should prove there were no erroneous readings.

[Bentwings]

I’m not sure he tested that way exactly. There was very low vac 10-12 In max. I’ll ask the exact number today when I call.
There was definitely low gage reading however.

[LeMarky Dissod]

There are several vacuum lines, mostly on the passenger side of the manifold and throttle body (not only the PCV lines), that are either hard plastic or junky rubber.
Many of these lines and connections can appear to the naked eye to be ok, yet are invisibly cracked or too stiff to hold vacuum.

The MAP sensor's nipple itself is also notorious for being too stiff to hold a proper vacuum.

[Bentwings]

Thanks . As I dont

[Bentwings]

Thanks. As I don’t have a convent place to work on the car I’ll take it to my son,’s shop some 60 miles away and look it over.

[Bentwings]

First I want to thank every one that’s trying to help me. Believe me every test that has been noted has at least been considered and tested if possible. I’m starting from scratch on this EFI I’d like to think y’all have taught me enough that I can struggle through this. This car should have been an easy one to learn on. It has not. And not to give excuses, I’m coming off a mild stroke, if there is such a thing. It’s left me with double vision in one eye so my typing is very difficult. Spell check try’s to help but misses sometimes. Thanks.

Well today he finally got the Buick back together and briefly road tested it.

It’s got new intake gaskets and valve cover gaskets, new O2 sensors, fresh anti freez.

I wasn’t there for this however.

He said It started perfectly, ran a few minutes but then when he road tested it was back to the same three cyl very rich, not as bad but enough to cause the cats to ignite excess fuel and pop slightly.

He said he scanned it and it’s ok except for the front cyl and the. back two on the psssenger side just like before.

So tomorrow after doc visit I’m going out there with my lap top and EEHACK and try and get a scan cold and one warmed up.
I can’t believe this as the intake was thoroughly cleaned, rodded out and blown dead dry. All seemed good.

I need the car I’m out of time. It’s dam cold here and I just can’t drive the el Camino any more. I need the wagon space and I hoped the cold weather starting ability. My buddy has a Camaro Z28 with the same motor and nearly the same mileage and it starts effortlessly at -25 f.


So I need more ideas.
Is it possible to have bad valve seals/ guides? With unmetered air coming in.

It’s obviously getting unmetered air from some place. But where?

Any air coming in the intake is metered and fueled according to the computer program. The O2 sensor reads only oxygen, no other products. According to what I’ve gathered here and on other forms, the O2 are seeing too much oxygen I.e. lean mixture, therefore it’s asking for more fuel but the computer has a max that it will allow on that bank. So this means to me that unmetered air is getting in somewhere and causing a false indication. I’m sure there is a less wordy way of saying this.

Now the test would be to disconnect both O2 and run pre programmed, open loop I think. Never the less with no information coming from the O2. There may be a code , I don’t know without trying.

One other detail, I believe EEHACK a,lows you to force open loop or running without 02. It also allows clearing the fuel condition and clearing the BLM back to its default. 126 I think. Must disconnect the battery to do this. I have not done myself...no car can’t test.

The man has been very good to me working on the car after hours and not charging except R&R of new parts.

Again I’m out in the cold with no convent place to work on my cars. It’s 10 deg f and 20 mph winds down here on the water front.

Byron

[steveo]

force open loop and if it runs 1000x better at least you’ll know what to focus on....

[Bentwings]

Thanks, that is what I want to focus on. He was going to unplug the O2 sensors tonight and unhook the battery. Then hook the battery only back up in the morning.. EEHACK also allows the forced open loop.

I’d guess the CEL will come on but I’ll know what that is. I hope there is not a “limp mode” on this Vintage.



As a side, I went to two local auto repair shops and neither wanted anything to do with either the el Camino or the Buick. Their guys have no experience with carbs or OBD1. I even offered to operate the EEHACK for him.

I also called two hotrod shops, one is in the process of closing the doors and not taking new work, the other didn’t do motor work, just fabrication.

[Bentwings]

@#$&%. ......I’m absolutely lost . He did exactly as noted. Unplugged both O2 sensors, disconnected the battery. Let the car sit over night. Hooked the battery up and started the car. THE SAME @#$&% PROBLEM....NO CHANGE.

WHAT THE .......IS GOING ON.?

I’m frustrated beyond belief.


Can there be an ignition issue? The Opti Spark is new old stock. New wires new plugs.

If there is an intermittent misfire, could this cause this? The mis fire would leave excess oxygen in the exhaust. However , with the O2’s not reading, why do I still have a very rich mixture? The computer has no feed back with the O2 disconnected..
Say 700 rpm divide by two= 350 sparks per minute, divide by 8 = 43+ sparks per cylinder in one minute. So you might not feel an individual mis fire, probably not even several misses if they were not aback to back',' this might be enough to cause the motor roughness.

It would take a ‘scope tester to see this. Now.. the guy just received the SnapOn addition to his new scanner that will allow this to be seen.
I have to call him back shortly to see if he was able to test this. He said he would work after hours on this again. He really wants the car out of there but not until it’s right. He is even more tenacious than I am.

Let’s do some logic,
If the cam were flat (it’s a stock roller), the cylinders would not fill completely but in open loop the computer would inject programmed fuel causing a rich mixture. With no O2 to modify it it would stay rich. low oxygen content, Correct?
How would the BLM affect this ? In closed loop the O2 would indicate excess oxygen because of incomplete burning of available fuel.the BLM would attempt to correct this by inrichining the mixture, but but it would be an error because there was no fuel to be burned.

I’m probably wrong altogether and just over thinking the situation.

JUST WANT THIS @#$&*% THING FIXED. IM about ready to replace the whole motoror just part the car out. Wirite the whole thing off as a bad deal. People lose more in depreciation the moment they drive out the door on new cars. Sadly LOL

[kur4o]

On the right and left side disconnect all AIR pipes that comes out from the exhaust header and plug the holes on the header. It is very likely the air is sucked from there.
It could also comes from the exhaust header egr pipe so check that one too. You need a massive amount of fresh air for the pcm to act like that.

[vilefly]

The O2 sensor wires (harness side) both should present .45V on them when unplugged. Left/driver's side = Purple/White, Right/passenger side = Purple. Make sure measured readings match scan readings. Check this without starting the car.

[lionelhutz]

Each 02 controls the fueling for the whole bank. So, I find it very hard to believe that the fuel trims can cause a single cylinder on one bank to go rich. Same with causing only 2 cylinders on the other bank. You need to figure out what is wrong with those 3 cylinders. Did you try swapping those injectors to other cylinders?

[Bentwings]

Since I have to pay for labor it was more practical to just replace the injectors with new rather than swap around.

That was the only change however the front cyl and rear two on the passenger side remained exactly the same on the SnapOn scanner. The second cyl is just slightly leaver. So you are right the entire bank is showing rich.

The left bank is reading fine. We did swap O2 sensors then replaced them with know good ones. No change at all.

I had him disconnect the battery and both O2 sensorsovernight. He then hooked the battery up in the morning. We were hoping it would run open loop, not using the O2 . However while it ran slightly better it still showed the right bank rich and pops in the converter.

While the intake was off he inspected the ports with a bore scope as well as bright light, looking for deposits or anything else that might cause problems.

I’ve suspected an ignition problem for awhile. Even though it has a new Opti, new wires, new plugs. He said he just received the optional spark tester that SnapOn has. He said he would try and get it hooked up so he could test that end again. Apparently this addition allows looking at spark for presence, operation and condition similar to our old oscilloscope.


I asl asked that he review the exhaust system, especially where the AIR pump fittings are. He had plugged them earlier but I wanted a review of this.

I appreciate everyone’s comments. I’ve had him look at virtually everything noted here but nothing seems to even touch the problem.

I’ve also checked numerous repair shops around her and they won’t touch the car as it is OBD1 even I bring my EEHACK computer to test with. Their mechanics only know OBD2. I told these places I will not stand for “ Throwing parts at it, hoping they guess the solution. I want to see and know the problem. They just run me out the door.

Maybe I’ll know more Monday morning.

FRUSTRATED.

Byron

[vilefly]

Hmmm. "Pops in the convertor". Sounds like he thinks there is a misfire on that side. Only a gulp of air can make it pop like that, either from a misfire or an exhaust leak. I wonder if he decided to swap the spark plugs from left to right to see if the problem moves. The swapping of the injectors has already been done, if I recall....twice. He might be the victim of a cracked spark plug, which seldom shows up on a scope. Sometimes the simplest things are the most elusive, especially since OBD-I has no misfire counter to access.


Have him try that and see if his hair falls out when it works.

Another diagnostic method on diagnosing low engine vacuum is to put scope on the MAP sensor, and watch for uneven peaks in the waveform. Anything that does not match the others is suspect. Crank up the sensitivity till the waveform fills the screen. On the second channel, use the inductive pickup, and use that signal to identify the cylinder that has the problem, allowing for the 4 cycles to take place on time. It has helped me bust lots of "rocker arm adjustments" that were done so very wrong. Overtightened rocker arms hold the valves open, and cause many issues, such as burned valves. It still amazes me how everyone gets this simple adjustment wrong. This happens to the small block chevy exclusively. Sometimes, a cylinder leakdown tester can miss this, due to the lifters "pumping up" slightly when the engine is in motion.

[vilefly]

There was a tool invented for the automotive oscilloscope that was basically an optical mouse encoder wheel attached to the end of a probe. The probe wheel was pressed against the belt to spin it. Lots of probes were killed due to butterfinger syndrome. Its digital output was converted to analog before put on the screen. This device, in concert with the traditional ignition pattern, would identify a weak cylinder/misfire based on crankshaft acceleration. It worked fairly well, provided you knew when and which cylinders were firing on the indicated pattern.

With the advent of misfire counters, this probe is now obsolete........but I still have mine. heh.
Figured I'd mention this tool in case anyone wanted to build one.

[Bentwings]

Villefly, the car is on the third set of new plugs. The right bank fouls them. Yes, they have been cleaned . We probably should have just used a set for testing.but each time we thought “finally fixed” so they were left in.
The converter pops are random but excess fuel and air are getting in and when it gets hot enough, it pops. That part is not what I was getting at about the ignition miss fire. This is possibly a separate issue. Hopefully hid new equipment will be able to test for this.

The plug wires were checked before installation for resistance and continuity.

[Bentwings]

BTW, My hair has long since fallen out, he is much younger than I but he is rapidly losing his hair over this project.

I really just want to get the car back. I can take it to my son’s repair shop and park it in a corner. It’s a 60 mile drive each way but if I spent all day there I could do that.

I want to run my EEHACK and compare scans.
I’m not sure if the fuel map can be edited enough to just over ride this thing or not. It may not even be the way to go in the first place. There is a hoist so I could get under the car as required.


It seems to me that it would take a substantial air leak to create this problem. The mech. Has inspected the exhaust manifolds and pipes. My diesel truck had a crack in the exhaust manifold about 4 inches long and big enough to put .035. Welding wire in it. You would think it would have affected the turbo boost a little but I didn’t even notice any loss of boost.

After the intak gasket change on the Buick there was little difference in the problem. The gaskets looked fine to me.

[Bentwings]

I’m at a total loss for this problem.
He disconnected the battery overnight and unplugged both O2 sensors. It ran exactly the same. He had not disconnected the AIR pump line in the exhaust so he did that and retested it. Same thing three cylinders are dead rich one is very near .


I don’t where to go now.

This issue started when the left cat was replaced. It had developed a very rich condition on the left bank , driver side. He said the Cat was bad so the left Cat was replaced .

Right here was when the issue switched to the right bank. This is the puzzle piece. Why did the condition switch sides?
This has been the question constantly asked through out all the testing.

We then replaced the right Cat, since the car had 110 k on it. I still have the old one.

I’m going to get the car back and run EEHACK as y’all have noted.

Question here is resetting the BLM. do I do this after hooking the battery up but before starting thr car or while the battery is disconnected?.


The compression test was very even. I don’t have s number but he said it was good. I would think a cracked piston might show low on that cyl. But I have take sbc apart that ran fine with several cracked pistons.

I asked awhile ago above if very bad valve seals and guides might be causing this.

Byron

[NomakeWan]

You would reset the BLMs with the battery connected and the key in the run position but the engine off. Connect with EEHack, click Control, then click “Reset BLMs.” This will Reset all BLMs to 128–assumes stoich of 14.7.

Running the car after that it should become obvious very quickly if your rich condition is real by watching the dash in EEHack. Best of luck.

[myburb]

I am only obd1 so not up on these systems but have been watching this for quite awhile. Would it have been an idea to reset the blm before pulling the o2s. I would think that would allow it to start on a uncorrected original ve table.

[Bentwings]

Thanks. Thats the exact information I needed. I’m not sure if this is how he reset using his SnspOn scanner. I’ll ask when I pick the car up.

[1project2many]

three cylinders are dead rich one is very near
Please tell us (again if necessary) how you are determining this? There is a level of detail here that seems impossible. It's like reporting measurements to the hundredth of an inch using only a carpenter's measuring tape. The most likely way to determine this is to measure unfiltered O2 output with a scope concurrently with injector or ignition pulses for a cylinder based reference. If you are relying on individual cylinder injector trims to determine rich/lean operation you will be led astray.

[vilefly]

When the catalysts were replaced, was either one broken up or missing a honeycomb element? If so, a piece might be left inside the muffler to clog up one side, and lower engine vacuum. Cut off the exhaust (or drill a 1/2 or larger hole) on the straight run prior to the muffler, but after the converter, and then look at your readings to see if they improve.

Just cut in a spot you know you can weld it back together.

Spoken from experience.

[vilefly]

Please tell us (again if necessary) how you are determining this? There is a level of detail here that seems impossible. It's like reporting measurements to the hundredth of an inch using only a carpenter's measuring tape. The most likely way to determine this is to measure unfiltered O2 output with a scope concurrently with injector or ignition pulses for a cylinder based reference. If you are relying on individual cylinder injector trims to determine rich/lean operation you will be led astray.

I think they are doing the old fashioned "read the spark plugs" method. This is my guess. Whomsoever wields the answer, wields the power of one can of pop.

[lionelhutz]

the front cyl and rear two on the passenger side remained exactly the same on the SnapOn scanner. The second cyl is just slightly leaver.


This says the rich cylinder determination came from a Snao-on scanner.

I still don't understand this or what he was looking at. There is no individual fuel trim on this LT1. There is no scanner data that would tell you an individual cylinder is rich.

It harder to fix something with the person trying to fix it doesn't know how it works.

[1project2many]

There is no scanner data that would tell you an individual cylinder is rich.
I agree. I also know from using a Snap-On scanner for many years that they do not always have correct data for a particular ecm. And the vehicle being worked on is so old Snappy has no interest in updating it.


Whomsoever wields the answer, wields the power of one can of pop.
It's killing me. There's more suspense here than between episodes of Breaking Bad.

[steveo]

there are four choices here since you've gone so far and run around in circles and found nothing

#1 go back to the beginning and forget everything, redo every test that's been done and don't use any original diagnostic data. you have no idea what subsystem is causing the fault, or even what the fault is, so you'd need to determine that and diagnose things in a tree shaped flow chart, there's a reason every service manual has logical trees for workflow.
#2 cut your losses and go buy a wrecked car, swap the engine, wiring, and ECM. save all the new parts you've put into the other engine.
#3 sell the car as 'needs tune up' and it's someone elses problem or profit or whatever, use that money to buy something that's already running and more reliable
#4 hire a real mechanic to find the problem

these are in order of hardest to easiest, but what they will cost you depends both on your negotiating skills and current market in your area. the lt1 is over 25 years old and despite what condition its in, it's going to require constant fiddling and tinkering.

[Bentwings]

You are absolutely right.
I got the car back today and drove it 60 miles over various roads and uphill and down hill so I have a fresh feel for the the way it performs.

It’s got a dead miss on the right bank. It idles rough but steady. Does not overheat or under heat. It does not like to operate in 4th under 60 mph if there is any load like a slight hill.you have to manually down shift to third. The trans seems to perform correctly in that it will downshift if you keep giving more throttle.The car feels like it wants to run but it’s being held back. Gas mileage is terrible.

So I agree we are going to square one like a new project problem. We will test everything and take notes on a fresh note pad. I even got a new pen.

I’m very suspicious of the OptiSpark right from the start.
I’ve already looked at several videos on testing the Opti but what is lacking is exactly what happened. There was a misfire that got progressively worse but what was shown on the scanner was not mentioned. The tester used was a device that could vary the resistance the spark had to overcome the gap. Ok what if you closed the plug gap some amount? Does the Miss go away?
Since this unit was replaced due to an oil leak that leaked oil into the Opti possibly this has happened again. So I want to really get into this thing.

Question here is,, is it easier to get at the Opti by removing the radiator so you don’t have to fight tight quarters?

[spfautsch]

I’m very suspicious of the OptiSpark right from the start.

My recommendation as it relates to the optispark is to pull it and check the trigger wheel for arc holes caused by coolant infiltration. It would take a really massive oil leak to cause a problem with the opti, but if there's coolant getting in the housing you need to first make sure your trigger wheel is intact and then fix your water pump. An arc hole in the trigger wheel could cause grossly retarded spark fire on the cylinder adjacent to the arc hole (causing a dead miss), but the rest of the cylinders would run fairly well.

Edit: after some thought, I believe arc holes in the trigger wheel would very likely set a code. Whatever the case - considering the work involved to get at the opti, I didn't mean to suggest diagnosis by way of "throwing parts at it".

With that said, I would strongly recommend the "start from square one" methodology mentioned by steveo. Your mechanic was either grossly mislead by telling you 3 out of 4 cylinders on one bank were "dead rich", or he was feeding you a busload of bullshit.

[1project2many]

The tester used was a device that could vary the resistance the spark had to overcome the gap.
I use spark testers frequently. But for your problem I believe you may need other methods. An inductive timing light can be a great tool to check for consistent spark. Connect the light using the coil wire instead of a plug wire and the light will be triggered every time spark is generated by the coil. Your eye is good enough to see any missed or doubled pulses caused by an ignition problem. If the leads are long enough you can take the light with you on a road test. Aim the bulb at a piece of paper in the car so you can watch the flashing while the misfire is occurring. If the light is blinking consistently you can then move the inductive lead to a plug wire and drive. Check each plug wire one at a time. If the light flashes for every wire you should discount ignition and move to fuel or compression. If the light doesn't work correctly at one cylinder you should check wire integrity and plug condition then suspect the opti.

[vilefly]

Measurements to take:
1) cylinder leakage test (not a compression test)
2) vacuum reading at idle (does it fluctuate too?)
3) results of spark output test per plug wire (also test ignition coil separately)
4) exhaust backpressure test per side (in PSI)
5) fuel pressure KOEO and KOER (does it bleed down?)

get lisle #20700
14841

get backpressure tester
14842
And......remove nothing except the spark plugs and o2 sensors to do the tests. Be efficient.

[Bentwings]

I really appreciate the help here.

There is a new water pump that was installed when the new Opti was installed. Yes there was a huge oil leak in the Opti because of a bad seal. I didn’t actually see it however. Looks like a gasket set is in order at least. We’ll get to the Opti as testing progresses.

My son has an adjustable spark tester as well as a leak down tester he uses on the funny car. So we can do those tests we’ll have to get the car on his hoist so we can mark the damper or at least measure it and I’ll get a tape. I don’t have a back pressure tester but I think a very low pressure gage could be fitted toe exhaust pipes. Jut drill for 1/8 npt and carefully tap. Easy to plug afterwards.

I’m concerned with intermittent spark. So some way to check that. There’s about one spark per second (check my math) so it’s possible to see a misfire at idle if you watch the sparks carefully. You could get with a timing light if you can guarantee the pickup.
My son has fuel pressure tester kit. So we can do that.

Some of the other tests are going to be a bit more involved but we’ll try our best to to run each one and document results.
I know this is going to be a tedious process but I want this car fixed, once and for all.

I’m just getting ready to run the car out to my son’s shop.We’ll try a few basic tests today. He may want to do a preliminary road test to get a feel of the issue beyond my description.
Byron

[vilefly]

The o2 sensor threads are 18mm x 1.50mm pitch. Find a bolt, drill a hole in it, npt tap, install brass nipple....done. Tool for life.

[steveo]

It’s got a dead miss on the right bank.

woah there.... back up. how did you determine it was a miss simply while driving? what does a miss feel like? and then how did you determine what bank was missing?

do one test at a time in logical order, you're already completely polluting your diagnostic process by assuming you know what's going on or where the problem might be located it. you've already whizzed right past the cause several times.

i'm not convinced its a miss. convince me.

maybe through convincing me you'll realize some things you need to check

[steveo]

also you have eehack, right? where are the logs? show us a log of where it's acting up and we'll rule out a lot of stuff for you.

[Bentwings]

yesterday I drove the car out to me son’s shop. It’s 65 miles mostly freeway. I was able to run solid 70-75 mph excep a few miles at 55-60. I used cruise control for the first time as an experiment to see how it handled the lack of power. You could feel a shudder on the level and when it required power to go up hills. Sometimes down shifting to direct. It took a lot of throttle to maintain speed. About a mile from the shop the check engine light cane on.

We let the car cool off before checking it over.

Drove it into the shop with a heavy miss. The car was shaking and very smelly exhaust from the right side.

We decided to just look over the motor for errors.
Found EGR vac line disconnected.
Fuel pressure regulator disconnected.
MAP sensor gasket mangled and leaking.
The three vac lines that run from the manifold right side to a connector block have cracked and leaking connectors.
Three wire harnesses were not routed correctly so we fixed that . Not a performance issue.
The O2 and spark testers were loaned out, they will be back today. Then test each separately.
Cyl 2 and 4 are weak. We’ll test the injectors tonight of tomorrow. The
Vacuum tested at 16 inches at idle. Rock steady.
The Optima yellow top is going to be gone. It’s weak.

I admit to not having a lot of experience with this system. That’s why I’m here. I've already learned a lot from y’all and I appreciate the help.
As far as scans I’m new to that too since I haven’t had the car for over 6 months. We spent a good part OF the afternoon going over EEHACK. My grandson who is a mechanic and body man grasped it pretty quickly. Once we get these basics fixed we’ll create some usable scans. I have a neat memory stick that works on my iPad plus a dedicated one for thr buick and EEHACK and it’s computer. I’ll post them as we get them. It may be the week end before I get out there as I have doc appointments this week. I have one shortly so I must go now

[steveo]

Cyl 2 and 4 are weak.

if cylinder 2 and 4 were truly weak, why no fluctuation in vacuum? how are you testing them as 'weak', by pulling plug leads off?


Fuel pressure regulator disconnected.
MAP sensor gasket mangled and leaking.

yeah that vac line to the regular does needs to be connected, and vacuum leaks are bad


The three vac lines that run from the manifold right side to a connector block have cracked and leaking connectors.

you have lots of vacuum line issues and the visual inspection might have missed something. disconnect everything that's connected to the intake manifold and test each item for vacuum holding (mityvac or similar). if you don't have that, disconnect everything from the intake manifold and cap them off securely. you only need fuel pressure regulator and pcv but you could leave the pcv hanging temporarily, it wont hurt anything.


About a mile from the shop the check engine light cane on.

what's the error code

[Bentwings]

#2,4 were shown weak on the test using EEHACK. Interesting that the other guy said 2,6,8 were weak with #4 not far behind.

We haven’t pulled the plug wires off yet but will. Their spark tester should be back tonight so that will get tested soon too.
I’ll ask also if my grandson noted the manifoldvac on EEHACK And if there was a number. I noted 10 inches earlier in my own test

We were doing as you noted, checking every connection. Both ends where possible.

Unfortunately I didn’t see the error code. It may have been cleared while I was doing something else. I’ll ask tonight when I call out there.
They will continue on it while I’m gone. I asked that they record everything no matter how small.

[Bentwings]

Sorry for this simple question but I have not done this before.
When I get ready to post scans. Can I just copy them and post them here or do I need to do something else?

[NomakeWan]

Eedata files should be zipped so that they can be attached to your post.

[steveo]

that cylinder strength thing is one step in diagnosis. it does not actually confirm a weak cylinder. test properly

[vilefly]

I forgot one more test: the RUNNING compression test. It is a bit of a pain to run (hot engine), but can reveal some things that can be missed on a cylinder leakage test. Lifters that are pumping up too far (but only with the engine running), and holding a valve slightly open.
Had it happen to me when somehow the lifter lost its wire retainer for the pushrod cup, and had unlimited travel hydraulically.
Hopefully, the intake leaks are sealed now, and a second vacuum reading is in order.

[steveo]

running compression test on stock b body manifolds isnt a realistic undertaking at all

the problem you describe would show up on a vac gauge for sure

[vilefly]

There are other problems it finds, and will confirm a cylinder leakage test. My tool bill is unrealistic, though. Tons of one-time wonders at my disposal, but it gets me there. If it were a trans am, I would agree. The b-body manifolds are a cake walk compared to the wretched sports car.

[Bentwings]

Thanks for the tip on posting files.

our plan is to go over everything externally and use EEHACK to guide us with electronic issues. Then we’ll get into more mechanical issues. This car ran perfect for 6-7000 miles then over night began with the problem.initially I thought it was a transmission problem but it really does work perfectly..maybe not as I would like but as it was designed.

Dang, I accidentally closed this before posting and lost it. I had s stoke a bout a month ago that has left me with some double vision up close so typing is a challenge. As I have to select letters where I can’t see them.

Anyway.it snowed 6” of wet snow last night so I didn’t go out to the shop.
My so got a new MAP sensor as the gasket was mangled on the original one. We straightened it out some but it was cracked and I dint want an issue back on the car. It still works but it is a question mark.
The car idles smoothly as far as the rpm reading but you can hear themiss and feel it at the exhaust pipe.
He was going to get another pair of O2 sensors as he feels these are not right. On EEHACK if you look at them the trace is a very jagged line. Those of you that had penmanship in grade school will remember the lead in to cursive writing. LOL

We spent most of the afternoon just going over the motor, looking for issues externally. We found several connections not connected and harnesses not in the proper place. The plugin with multiple vacuum Lin’s has cracked lines so my son is going to try to get a replacement. Otherwise we’ll figure out alternate hookup. The fuel pressure vacuum line was not hooked up the EGR vacuum line was not hooked up and another line I forgot what it was also not hooked up..
At least the oil was changed as I had requested months ago.

They were going to work on it last night but I didn’t hear from them probably due to the weather. I won’t get out again until the weekend
He should have his test equipment back then too.

here are a few pictures.
the first the missed fitting is to the left and down just a little.
the second is the MAP sensor gasket safer straighting the best we could.
the third might be the fuel pressure regulator, not sure however.

these are just a few or the things we found. Over all I’m greatly disappointed on the work. I know I got a deal on it but ...the old saying you get what you pay for. As old as I am I’m still learning my lessons if life...sadly LOL
BYRON

[vilefly]

Sounds like the other guy.....let's just call him 2-cycle-john.....was in over his head. I wonder if carburetors frighten him. I just hope the vacuum and vent hoses to the distributor are still in place.

[Bentwings]

That line is in place and clean. My son just reported that the spark test was great. It maxed out the tester and he even got juiced once by it. So good news there.
My grand son likes the EEHACK. He likes that it allows editing but he says he won’t do it until he has his own . Might be a while as they are Ford guys.

The vacuum line in the picture was also open...not hooked to anything. I’ll have to ask where it was supposed to be connected or if it was just a blank and supposed to be plugged.
They won’t get to do any more until Friday.

[steveo]

you really can't even begin to work on this car without isolating the engine from any suspected bad vacuum plumbing. having open hose barbs on the manifold definitely will cause the engine to run horribly.

that map sensor seal actually looks kinda normal, they're always a bit squishy but rarely leak. if you wanted to buy just the seal itself i have a mercury marine part number for it somewhere, it's a few bucks, for some reason it's hard to find in the automotive world.

[steveo]

My grand son likes the EEHACK. He likes that it allows editing but he says he won’t do it until he has his own . Might be a while as they are Ford guys.

eehack doesn't really edit anything (besides flashing new bin files). the changes in the control section are temporary and go away when you disconnect or restart the engine. they're totally safe.

[Bentwings]

Thanks for the info. I looked up much of your sig. and passed this on to my son and grand son.

The gasket was much worse than the picture. We straightened it out enough to continue testing. It would be nice to have a spare on hand.
They may be working on the car now. I’ll know more tonight.

[Bentwings]

Well, good news for a change.The new MAP sensor got the vac up to a little over 16 almost 17 inches. Then adding tested and known good O2 sensors got it just over 19 inches at idle. My son says it runs much better. He is going to put a few miles on it tomorrow and see if it cleans out a bit. Then they will put the scanner on it and record where we are at. I’m curious to see what the new O2 sensors look like on the scanner. The air cleaner only has a few miles on it so I think we’ll leave it alone.

I don’t know if they put a fuel filter on or not but I think it would be a good idea.
p
If all goes well I’d like to fix the right exhaust pipe. It looks like it got hit by something backing up. It hangs down too far and looks terrible. Not a big deal but I just don’t like exhaust pipes that face the wrong way. I really hope it’s finally fixed. It’s going to get brutally cold next week and more snow. The el Camino is just a handful in the snow that I don’t need.
They are going to try and bring the car to me then take the el Camino back and fix the idle, change oil and a couple other fixes I’ve had to delay.

So that’s it for now.
I want to thank everyone for all the help and tips and tests. I hope this finally fixed this car. I’ll know more
tomorrow afternoon.

Byron.

[vilefly]

Looks like 2-cycle-john is out of a job. Failed miserably in his work. Didn't even find a single vacuum leak, and you guys found them all. He is so fired. No worthy of his own scan tool which would have told him about an inaccurate MAP sensor reading KOEO.

[Bentwings]

I’m bending over ready for the butt kicking. My son drove the car around quite a bit today but it started missing again. He parked it in his shop to cool off. After a couple hours he tried it again. It started right up and ran fine for about five minutes then started missing. So he shut it off and let it sit for awhile. Grandson noticed AF leaking all over. So they raised up and it’s pouring out of the “new water pump”. So they pulled the vacuum lines off the Opti and AF drained out. They blew a little air through it gently then started it without the lines. It ran fine but water was still pouring out of the water pump.

Give me a boot. I had a new WP install so it would not be a problem later. Supposedly a new old stock Opti too. Looks like I got taken to the cleaners. I told them to take pictures before they fix it. And take a scan from cold start until it starts missing. I need the car and I’m out of time. I’ll deal with the other guy Mon.I know...ya all told me there were issues in the manner the testing was going.

I need to go outside and cool off. More later.
Byron

[steveo]

months of diagnosis work that starts with 'it can't be _____ i just replaced that' ends with 'it was the ______ all along'

[vilefly]

Time to make 2-cycle-john's shop public knowledge, so we can drop off small bags on fire on his doorstep. It's standard proceedure, you know. Sounds like he didn't replace a thing.

[Bentwings]

I’m back...now don’t every one run, I’m not contagious.

New water pump and Opti. Supposed to be good stuff.

I continued to explore solutions and come up with several.
Install piece of brake line in WP weep hole and JB Weld in place hook pierce of rubber hose to direct Leakage from OPTI. Im
Sitting here in my boat and it’s 5 deg outside light snow. Not that I don’t have anything else to do.
The second thing is to put a thin layer of silicone sealer around the cap joint.

I don’t have these parts in my hands so I’m going on other’s descriptions. The experts are here so is this the things to do?

I’m going out to my son’s shop this weekend to look at this mess. Fortunately he does have some experience with these things and is pretty good at repairing things to work right and for a long time.

He was going to take pictures tonight so I may have something to for show and tell soon.

[LeMarky Dissod]

… New water pump and Opti. Supposed to be good stuff.

I continued to explore solutions and come up with several.
Install piece of brake line in WP weep hole and JB Weld in place hook pierce of rubber hose to direct Leakage from OPTI.
Sitting here in my boat and it’s 5 deg outside light snow. Not that I don’t have anything else to do.
The second thing is to put a thin layer of silicone sealer around the cap joint.

I don’t have these parts in my hands so I’m going on other’s descriptions. The experts are here so is this the things to do?

I’m going out to my son’s shop this weekend to look at this mess. Fortunately he does have some experience with these things and is pretty good at repairing things to work right and for a long time.

He was going to take pictures tonight so I may have something to for show and tell soon.For the H2Opump, many from the ImpalaSS Forum would install a zerk fitting into the weep hole with a rubber hose to do the same thing.

As for the Opti-Spark, there are several things that can be done. Since the ISSF got 'upgraded' with xenforo, their search function doesn't work well, but I found these with duckduckgo:
https://www.impalassforum.com/threads/protecting-the-optispark.1260065/
https://www.impalassforum.com/threads/opti-shield.1240578/
https://www.impalassforum.com/threads/idea-for-protecting-opti-better.256775/
https://www.impalassforum.com/threads/which-delco-opti-to-go-with-i-have-2-choices.1312794/
https://www.impalassforum.com/threads/the-cheap-opti-thread.1303385/

A strip of scotch tape joining the Opti- to the -Spark works pretty well, it's what I'm doing. Some ISSF guys use a very thin bead of sealer, hopefully it'll come apart when it needs to.
One guy even went so far as to paint over it with some kind of blue coating that easily peels off.

Don't forget about protecting the electrical harness on top of the engine, as well as the connector that goes directly to the top of the Opti-Spark.

[Bentwings]

Just got the new Opti and water pump. I just talked to my son and he was already thinking about the weep hole he will come up with something. He also is going with the sealer in the cap. It’s not hard to get off if need be.On one of the threads above they noted some kind of shield to deflect most road water. We loook at that too.
he aside the temp sensor wire was pinched at sometime so he got a bew one. Apparently easy to damage. It’s possible this may have caused this whole problem or at least contributed to it as this leads to the ECM. I never heard the electric fan running but I don’t think it comes on until a much higher temp. I think the temp thing might be a temp switch rather than a sender . I used the switch type to drive a relay to run the electric fan on my Willys. It worked great. Also a sender to run the temp gage.looks thick that’s how this works. We’ll see they are going to look at my early scans to see if this was working. So I’ll add this to the complaint list. My butt is getting sore from y’ll kicking me. I don’t think I would have missed all this stuff even as a green hotn. It’s all basic stuff.
Well we are getting closer I think.ill run oth Sat or Sun to see how things are going.

[LeMarky Dissod]

If the H2Opump is prevented from peeing on the Opti-Spark, then the best road water shield you can make would likely be the painted on coating cited in
https://www.impalassforum.com/threads/idea-for-protecting-opti-better.256775/
which might even protect the Opti-Spark from literally driving partially submerged through a ludicrously deep puddle.
The 2nd best road water shield would be along the lines of a skid plate designed to shield the Opti-Spark from road spray.
Either way, don't forget to protect the connectors from seepage!

Yes, the wiring for the H2Opump temp sensor is notoriously thin & brittle, all too easily damaged. I think it works with variable resistance depending on temp. Anyway, it sends a signal to the pcm.
If disconnected, or wiring is bad, the coolant temp will read as -40°C, which will keep the pcm in open loop and enrich the fueling deep into porcine.
OEM LT1 fans turn on @ 225°F & 232°F for sedans and wagons, @ 226°F & 235°F for F-coupes, and @ 227°F & 235°F for Y-coupes, all of which are too hot for me - 203°F & 212°F is far better and safer.
You really don't need to reengineer this, just make sure that the sensor works & reads properly even when you wiggle the wiring.

[Bentwings]

I read somewhere that this is a switch rather than variable resistancedevice. In other words it turns on at a given temp. The tolerance noted is for manufacturing tolerance. It’s does go to the ECM and does control the turn on for the electric fan. The one on my existing WP is frozen in for good so a new one is ready for install with the pig tail.

[steveo]

there’s no temp switch on an lt1

there are two temp sensors

one on the front goes to the ecm

one in the cyl head goes to the gauge

the ecm controls the fan(s) with parameters

[Bentwings]

We’ll look into some kind of splash shields. I made some for my rl Camino that have been tail light savers. These cars are notorious for having the tail light wires ripped out in the sno/salt belt up here. So far I have not had a single tail light issue in all the slop and snow we have had. I would not normally drive the el Camino in the winter but I have no choice until the Buick is finished.

[Bentwings]

The butt kicking just won’t stop. My son sent some pictures but I’m having trouble saving them. The one with the corroded contacts especially went missing. They were bright greenish white, like clumps on each rotor contact


Here is a picture of the new vs the one taken off. Does this look like about 5-6k miles driving. Mostly town and country very little winter snow.? The new one comes with a pigtail harness.

The water pump looks about the same condition. Obvious leak and much oily grim.

[1project2many]

Hopefully this solves the problem. You can pull the cap off the distributor and look for signs of contamination. It may seem a waste of time, but after all the false starts and dead ends I would want the reassurance that the culprit apparent is actually guilty as charged.

[vilefly]

Looks like it was never replaced. 2-cycle-john strikes again.

What a scurvy shyster bastard. Not to mention the teflon seal in the timing cover was not replaced. I think this guy insults the rest of the human race by daring to walk upright shamelessly. Never trust a fat mechanic, I say. He needs to go on a date with 300lb Savage Lucy, with teeth like baseballs, a lumberjack's body, and eyes like jellied fire.....but enough about my ex. (some facts have been exaggerated to protect the guilty)

[Bentwings]

Believe me I have a list and photos to back it up. I’ll post more photos as I sort them out. Latest looks like only 4 plug wires were replaced and I requested all 8.
I kinda hate to list second hand stuff but I simply can not be at the shop while this is going on. Based on countless notes about sealing the Opti I specifically asked that this be done....not. My son said the o ring was rock hard. I’m guessing a junk yard unit was installed. That’s what it looks like. I’ve only driven the car 6k miles since got it and maybe less than 1k since this all started. How could this kind of grime build up on a new old stock part? Water plump goes out in well under 1k miles? There must be a dozen common fixes for the weep hole. It doesn’t take brilliance to see this is a problem when you have the dist in your hand and AF Is dripping out of it.

Y’all are right I got taken to the cleaners. I feel like a complete idiot. I never shouldhave let it drag on like this.
I’ll post more as we go. New plugs and wires, new idler and tensioner are on the way. These are just preventative things one is rough so both are being replaced. I’m stretcging but I’d bet the EGR valve was not replaced either.

[vilefly]

Don't replace without testing it, that is how you got in this mess to begin with.

[Bentwings]

I well understand what you are saying. The idlers are both shaky so it’s being done now to prevent having to do it at a bad time. The plug wires were original and very stiff. There will be a record of resistance values to add to my notes. There is no core charge on the water pump or Opti . I’m already 6 months out of time and I just don’t want any more problems. Especially ones that can be fixed right now. There just aren’t any places that will service my fleet. The one hotrod shop I would trust is closed. I know one other one that I’ve visited several times would do work but they are usually backed up a month of so. It could be and has been, get a more reliable car or truck. My mind set just will not allow spend in ding a lot ona new car. They still need occasional service too. And of course my boat gets pointed at. I happen to live on my boat so it’s like living right in your garage or shop. I can an do fix and service it as needed.

i don’t know about the EGR. once the car is up and running w will check it.

[vilefly]

I was referring to the EGR valve, which classifies as a subcritical component, and should not be a high priority unless the gasket has a vacuum leak around it. Everything else on your list needs replacing as you say.

[vilefly]

Guys, I found a picture someone took of Bentwings. Here's what he looked like on christmas...

14962
He was muttering something about burning a bag of coal on a doorstep, I think.

[Bentwings]

Haha that’s cute.

From what my son said the car is done snd runs so smoothly you can hardly hear it run. He said it didn’t make one revolution to start after all this. I’ll get a few good scans right away for reference. I have to say the EEHACK and the little laptop I got for it have been instrumental in servicing this car.
I’m going out in the morning to pick it up. I plan on posting som pictures of the junk that was removed and replaced. Hopefully I can get clear enough pictures that others can comment on. I’m really disappointed that the first guy couldn’t fix this car. It appears that the main issue was the water pump leaked and ruined the Opti. Both of these were replaced in the first go around. It’s hard to believe the “new water pump” could immediately fail. The car didn’t run well after these were replaced to begin with. I only drove the car about 1000 miles during this whole process. I’ll post pictures of the “new”Opti and the “new” water pump. Then we’ll look at the plugs and wires that were supposed to be “new” . We are are still trying to find a new pulley with the bearing. I don’t know if we can just remove the bearing. I’ll look tomorrow.none of the local parts stores even have it listed. Any suggestions would be appreciated.

I want to thank every one for all the helpful information given here.
Byron

here is the inside of the Opticap we removed. Not cleaned or touched.
im having trouble with pictures so I’ll wait until later.id just like observations...t see if I agree.’ll comment later.

[kur4o]

Bentwings,

It is nice that in the end it is all good. It was a good diagnostics workshop for all of us.

I remember that you mentioned the PCM was changed at some point.

Steveo the creator of EEhack needs a test PCM to develop more features to the already awsome program. If you still have that spare PCM can you borrow it to him.

Thanks

[vilefly]

If it is a metal pulley, you can drive out the old bearing to replace it. You will have to read the number off the bearing itself, and type it directly into google for results. I can't remember the number, (6502 or 6205, etc) but it is a common bearing used for nearly all GM pulleys for many years. I had bought a dozen of them in case I had supply issues, but they are at the shop, and this is the weekend.

[Bentwings]

I picked the Buick up today and drove about 100 miles. I purrs like a kitten. When it’s running you can barely feel it neutral idle is about 700 in gear about 650.

I’ll post a couple pictures I took today. I’d like comments. The car has 117 k on it I’ve driven it about 1000 miles during this ordeal mostly travel to and from the original shop.

[Bentwings]

Well here is another tidbit.
A friend of my son has a hotrod caprice sedan. He is also a GM MECHANIC, TECHNISION.


He came by to see how things were going. He picked up a couple spark plugs that we took out and looked at them. He says “ the guy didn’t even put new plugs in”. Look at the ends these have a little dimple in the center. These only come on OEM GM CarsCARS from the factory..You can’t buy the dimple plugs only ones that are flat on the ends. We didn’t know this so I’m going to go over to the local Buick GMC dealer and ask ther, not to dispute but to verify. I suspect something to do with warrantee. I have pictures but I can’t get them into “pictures” from messages on my phone.

This story just keeps going on and on.

Byron

[1project2many]

Interesting. We always looked for a dot of paint on the OE plugs. Nothing aftermarket came with a paint dot.

https://www.silveradosierra.com/vortec-4-8l-v8/wrong-spark-plugs-from-the-factory-t219202.html#p2334498
https://www.silveradosierra.com/resources/image/thumb/237914

[vilefly]

I usually look at the other end of the plug to determine its worthiness. If there is erosion, (within 1k miles) then it was never new.

[Bentwings]

I under stand the business end of the plugs.

This car had OEM plugs in it when I originally brought the car to the guy. He determined that it was time for new plugs and I was charged for them. However it looks like these are the original plugs. Cleaned and stuck back in.I’m still investigating the validity or the statement about the dimple identifier.

[Bentwings]

One more small issue has come up.

When coming to a stop brakes on the motor or car “chugs intermittently. More of a jerk against the brakes.Not all the time however. Mostly when warm. Although it was -12 deg f and I did it then too. It’s like a single cyl misfire. So far no codes no check engine light.
It’s not a constant miss just intermittently when stopped with the brakes on. It seems to go away as some as brakes are released. Does not make any difference how hard brakes ar on. I also tested as very low speed and gently pressed the brakes. I couldn’t feel it or hear it. So I’m not sure if it’s just something caused by brake actuation or something else.

Possibly something going on with idle air control.from the looks of it this was not serviced by the first guy.although he must have removed it when swapping intakes.. the Opti is completely sealed and new vacuum lines installed. Brand new water pump. No leaks.new plug wires and plugs.it may be the AC compressor cycling but it’s very quick what ever it is. Possible momentary converter locking and unlocking.if you listen very carefully you can hear or slightly feel the down shifts when coming to a stop. Doesn’t seem be associated with these. To me it seams something associated with brake activation.

[vilefly]

We need to know what the IAC count is on a warmed up engine in Park and then in Drive. Should be 18-23 idling in Park, and about 24-30 in Drive, no climate controls turned on.

Then we can go on to see what condition the transmission fluid is in. Red with clutch dust, brown with clutch dust, black and burned? The smell of the fluid is important. If the IAC counts are nominal, then I wonder about the TCC solenoid sticking a bit. I have had to drive cars for about 20-30min above 50mph on the highway for this type of symptom to show up. Sometimes it is bad enough to stop the motor once, only to let the car restart with no idling syptoms. Clutch dust in the fluid usually is the cause....fluid change and filter will solve the sticking solenoid issue. It feels like someone driving a stick shift forgetting to disengage the clutch while hitting the brakes and killing the engine as a result. You symptom is milder, I think. Near-stall.

[Bentwings]

With great sadness I have to make this post.

First I want to thank everyone that contributed to helping fix this car. Ultimately I was fixed by going over every part using EEHACK and everyone’s suggestions. Each area of the EFI was examined and repaired or replaced. Untill the care ran perfectly. The last tank of gas got 23 mpg. Town and country driving it started in -15 deg weather like it was 70 degrees. It idled so we’ll it was hard to tell it was running. There was no smelly exhaust, no leaks anywhere no noises,nothing. All systems worked just like a new car. I give my son and grand son the credit for doing all the mechanical work on the car. Thinks that didn’t work properly were examined and problems found then fixed with a fix it correctly the first time not several times. The best parts available were used. Essentially the entire EFI system was gone over. So the car ran perfectly. Now the sad part . Over the last few years a number of my car friends have passed away from various things. I began thinking of my own situation after my first trip to the hospital where a new hole was drilled in my head and blood was drained out as a result of a fall. The doctors talked of stroke and said no more sports ,not even tiddlywinks. I can’t have another head injury. This led to stroke discussion. What they are, symptoms, causes and ultimately my medical position and condition. I’m actually in pretty good shap not smoking drinking or other bad stuff. However the possibility of stroke or blood clots. Do I m on blood thinners. Amounts checked weekly. As I began realizing I’m not bullet proof anymore the possibility of stroke while driving began to be my worst nightmare. Well sadly that’s exactly what happened. There was no warning. I simply lost vision for a couple seconds andBAM I hit another car. And a road object. I never saw it. I ended up in the ditch and totaled the car. It didn’t look bad at first but the frame was bent in a very bad place and deemed not safely repairable.we even found a parts car so all the damaged sheet metal could have been fixed. I’ve not had a single thing like it since. I have to be thankful neither me or my dog were injured but nobody else in the ither vehicle was hurt. It could have been very much worst. I was only going about 40 on a back road.

So the bottom line I want to pass on is be safe on the roads. I suspect this happens more than many realize. Even my doctors said the same thing. A stroke does not have to be a paralyzing painfull thing. Something as insidiously simple like blocked vision for a few seconds is all it takes. I had numerous scans that just did not foretell this. Well now I’m prevented from driving at all. Serious fall risk. Can’t work or very limited. Probably a hazard riding an exercise. Bike. Heaven forbid operating anything with wheels. Mobility is limited to walking with my service dog only. Then letting someone know where I’m going. All this almost overnight. Mentally it’s frustrating beyond belief. I’m probably going to be forbidden from going to funny car races that I like. I’ve been through two weeks of mental and physical therapy just to sooth my frustrations I guess. Just keep in mind these things can happen as you get older. No need for sympathy just everone be safe and enjoy your activities while you can. The enjoyment of all of you during this mess has been wonderful. I don’t mind a single debate or criticism. ,it’s all a learning process. I learned so much here that it amazes me that y’ll can be so much fun.

Thanks again for the help and enjoyment of a great bunch of guys.

Byron Nelson.

[1project2many]

Hi Bryan,

You're lucky and you realize it. This is a good thing. I work in a business where I frequently see people who believe that they are as bulletproof as they feel, even with existing medical conditions. It's scary. But the brain is not going to operate properly without enough oxygen, without enough blood flow. And a brain that doesn't operate properly or consistently should not be driving. I am amazed at the number of people who won't trust a highly programmed, fully functional computer to drive the car they're in, yet they trust themselves despite knowing "bad things" can happen. We humans are truly a strange species.

Hopefully you get to go to races, maybe take in a car show or two. You stayed with your car long after most folks would give up and I hope you find a way to continue to enjoy the hobby.

[steveo]

really sorry to hear all of this. i've witnessed from your struggles that you probably have the perseverance to learn to live well despite your newfound challenges. best of luck to you.

[vilefly]

Wow. Sorry to hear all that bad luck happened all at once. It definitely could have been much worse, for sure. Now, my evil plan to have you drive through the shyster mechanic's building, feigning the same symptoms, has been foiled also. We'll have to settle for a drive-by-fruiting, instead. Use an eggplant, though. But the real question is.....is an eggplant a fruit or a vegetable? Figure the best weapon is humor these days.

[sherlock9c1]

Bryan, it's a miracle you're even able to get on and type this. Never regret your journey, and the value of suffering. Thank you for coming back and posting. I commend you for your tenacity!

[1project2many]

BTW, I was just thinking about how much work your son did for you. It's good to know there are mechanics that take pride in their work. It's reassuring to read there are still some kids who take pride in helping their parents.

I will be grateful and proud if my son ends up with the same outlook.

[Bentwings]

Ya know, coming back here after this mess and now medical issues, then I get compliments as well as my boys. just brings tears to my eyes. It’s a feeling that just can’t be expressed as much as felt. So many of you waded through my rants and raves yet stayed the course. I just hope I can offer the one thing someone needs someday to get through a tough spot.be it cars or anything. I’ve had a good run as some say. There has been some bumpy roads but I just hope I can help just one person feel better as others have helped me.

Thank you all

Byron

[daveosx]

God bless Byron
just getting back to my email and saw your post.
I too am in serious health, kidney loss.
I have experienced the blacking out had to shutter my business 2018, Kind scares the heck out of you waking up in weird locations.
I stay away from the AMA mafia as much as possible
I found that because of my kidney failure my immune system decided to eat my thyroid gland.
The final episode was a 9 hour ordeal of 200/128 BP and 108F temp only on my neck.
I sat on my coach packed with ice and road it out.
The endrocinologist and the Androcinologist helped me figure out I was missing 5 proteins from my diet.
The passing out is not always stroke related or the TMS sometimes it can actually be an effect of many of the popular prescriptions, not in my case my kidney issues have advanced to the point that I was losing protein so fast that the metabolic krebs cycle was shutting down.
I stopped producing ATP the cellular glucose burner and instead only produced ACE2 and Aldesterone.
I have been on a solely organic diet for 14 years due to cancer in my wife.
To compensate for the protein loss I eat a hyper protein diet 160G per day.
I use desiccated pork thyroid to provide T3/t4 o produce ATP.
My point to all this that you should find a local anti-aging doctor and have a complete micronutrient study done.
Typically the study costs about $300 it gives you a great insight.
For instance my Heart was stopping because of a lack of ZINC and Potassium, Most of my muscle loss was from a lack of Pantothenine B5, Now to avoid dialysis I use a drug that causes hyperphosphorosis dilation of the Nephrons of the kidneys. So I have to supplement everything. I can not exercise due to lactic acidosis so I have to manage inflows and outflows.
Strictly through diet and supplements have have regained 30 pounds of muscle on my upper body.
I live a really sedentary life avoiding any exertion yet I am becoming very muscular and my energy is improving.
Please check with an anti-aging specialist because the AMA is a death cult.
FYI my doctors that let my health decline so far were Cleveland Clinic.

[NomakeWan]

I stay away from the AMA mafia as much as possible
Please check with an anti-aging specialist because the AMA is a death cult.
I'll take fun posts I never thought I'd have the opportunity to interact with on a forum dedicated to reverse-engineering old GM computerized fuel injection systems for $400, Alex.

[daveosx]

I'll take fun posts I never thought I'd have the opportunity to interact with on a forum dedicated to reverse-engineering old GM computerized fuel injection systems for $400, Alex.<br>
Hey the guy is having issues with passing out the AMA trained Practitioners will almost immediately go down their check list.
Blood Pressure---no
Heart Rhythm ---no
Stroke --- Unknown without FMRI ding ding ding Plavic doctor bonus $5 month, Seralquel $5 per month, WelButrin $25 per month.
SO the insurance pays the MDs for every test they avoid and pharma pays for every prescription written.
I know both my younger brothers are doctors.
As for me I was put in Hospice 7 years ago April because there was nothing Cleveland Clinic could "do for me".
After shitloads of research I found out about the Standard of Care website used by MDs contracted by insurance carriers.
If you put the patients SS# in the available treatments are provided once a diagnostic code is entered than the available additional diagnostic codes and treatment codes are made available for MDs to bill for.
I also found out that things like MERSA are being treated with Clindomycin and Vancomycin rather than Alenia because the doctors can not prescribe Alenia under insurance agreements.
It's 35 years old and $20 a pill. 5 pills cures MERSA.
So if your a cheesecake brainwashed MD that spent at least 3 years of your life in a residency deprived of sleep and in an absolute echo chamber you will take objection to the AMA being called the death cult that it is.
So another great example; what is the functional elasticity of senior lung tissue ?
Over 70 a persons lung tissue elasticity declines about 1-2% per year.
So if you have a median lung pressure of .5 atmosphere and a blood OX below 80 and your diaphragm is paralyzed then a ventilator set at 1.5A 2.5liters would allow you to sync and gain rhythm.
But if you do not have paralysis and your lungs are aspirated when your blood OX drops below 90 you should have 6L per minute CPAP not ventilator.
AMA and FDA approves influenza protocol for elderly shoots them up with Ketamine and Ventilates them into pulmonary thrombolisms marks it Covid19 and cashes out $54K.
SO death cult.
37,000 people died before anyone in the AMA even noticed!
Not every gearhead is slow minded just treated that way.

[daveosx]

What would you advise to use for a coil upgrade that won’t melt the opti ?

Thanks
Mitch

I just noticed this post like a year later
Coil voltage tapers off as the coil become saturated at Hi RPM so some guys opt for high voltage that tends to cause the cross arcing at lower rpm.
If my memory is correct I think that I use < 6.6mH primary with a 60KV peek above 6500 RPM and a regular Speedmaster below that..
https://www.jegs.com/i/NGK-Spark-Plugs/739/U1117/10002/-1 hi rpm
https://www.jegs.com/i/Speedmaster/746/PCE382.1007/10002/-1 Lo RPM

Nology Hotwires also work well with the NGK coil many people do not believe that they do anything but in normal driving they provide a store of energy in the inline capacitor on the wire lead. So as each low rpm firing pushes enough energy VA into the sparkgap it charges the cap so at higher RPM the cap discharges along with the lower coil output. Looking on a scope the area under the spark is increased using nology.
Many turbo and rice burner guys gap their plugs to .035 to get longer spark durations.
A lower resistance secondary coil with higher voltage increases the duration as well.
I found on the LT1 the gap is good all the way out to 0.10 with the Speedmaster coil and .065 with the NGK
Because caprice headers are tight I set the gap at 0.050 with the iridium AC delco plugs.
The Speedmaster coil gives you 1.5-1.7ms duration at that gap the NGK is about 2ms.
I have run the NGK coil in a waist spark setup with a crank trigger out to 7400RPM so the coil is about 60K times a minute.
On a non waist spark like the Opti the coil is only sparking 30K per minute.
Somewhere there is a calculator I think at Megmanual for mili henries vs Spark duration.
You have to adjust the Dwell of the EST to optimise.
The stock LT-4 corvette ignition module is like a ford TFI in that it measures the peak coil primary amperage and keeps it at 5.5Amp.
Later truck coil modules can be used to get higher current as well.
A 1996 GMC 7.4L HEI module connected to the ECM and coil works to raise current and adjust the dwell.
You do not have to use the reference signal you bring the EST bypass to ground and the EST and coil wires hook up the same as the LT-1 coil.

[NomakeWan]

I also found out that things like MERSA are being treated with Clindomycin and Vancomycin rather than Alenia because the doctors can not prescribe Alenia under insurance agreements.
It's 35 years old and $20 a pill. 5 pills cures MERSA.
What universe are you living in? Alinia is an anti-parasitic drug, not an antibacterial. It's used to treat protozoan parasitic infections. And hardly $20 a pill, its MSRP is $1027 but can be "found" for $800 for a bottle of 6 500mg pills. Considering it's both astronomically more expensive than you claim and is utterly ineffective against MRSA, I think I know where this is going...



So another great example; what is the functional elasticity of senior lung tissue ?
Over 70 a persons lung tissue elasticity declines about 1-2% per year.
So if you have a median lung pressure of .5 atmosphere and a blood OX below 80 and your diaphragm is paralyzed then a ventilator set at 1.5A 2.5liters would allow you to sync and gain rhythm.
But if you do not have paralysis and your lungs are aspirated when your blood OX drops below 90 you should have 6L per minute CPAP not ventilator.
AMA and FDA approves influenza protocol for elderly shoots them up with Ketamine and Ventilates them into pulmonary thrombolisms marks it Covid19 and cashes out $54K.
SO death cult.
37,000 people died before anyone in the AMA even noticed!
Not every gearhead is slow minded just treated that way.
https://www.youtube.com/watch?v=oLoaLODus_4

I highly suggest a bottle for you, good sir! Cheers!

[daveosx]

What universe are you living in? Alinia is an anti-parasitic drug, not an antibacterial. It's used to treat protozoan parasitic infections. And hardly $20 a pill, its MSRP is $1027 but can be "found" for $800 for a bottle of 6 500mg pills. Considering it's both astronomically more expensive than you claim and is utterly ineffective against MRSA, I think I know where this is going...



https://www.youtube.com/watch?v=oLoaLODus_4

I highly suggest a bottle for you, good sir! Cheers!

I actually am from this universe not the one you must be from

Alenia not Alinia and it is 100mg at $20 per pill does not even show in AMA FDA look up online other than a mention of it's ingredients.
https://www.drugs.com/international/alenia.html

NOT the cryptosporidia drug

And it has successfully treated 4 persons I know of, one was on Vancomycin before I told him about it.
He stopped treatment his father ordered the Alenia and he no longer has MRSA.
This is one of the benefits of diversity much is known outside of academically accepted US medicine.
In countries other than the USA people of means do not drop dead in the streets, many many options exist to treat untreatable by AMA illness.

SO I suggest you roll up your sleeve and get what the hell ever they want to push next.

[daveosx]

You know NomakeWan my post that you decided to troll was one of comfort and positive option for someone who has had the misfortune of illness.

I can see that you missed the fairly obvious condolences conveyed along with my personal experience.

While it has nothing to do with reverse engineering the work I helped on at GM back in the early 1990s it was an act of friendship towards another human being.

If that challenged your widely accepted posture of belief it opens yourself to ridicule not I.

I largely have abstained from contributing to public forum because of the inevitable argument that emerges on any open discussion or flow of human contact when individuals select to use accepted memory of historical teachings as a source of authority. History and the mastery of history does not provide authority only mastery of a common set of beliefs. Academic accolade being substituted for knowledge is merely a conveyance of power not authority. Power is protected by force not authority and seldom is history truthful.

The AMA began with full and absolute knowledge that Doctors being of good character did not have to wash their hands.
It also fully supported tobacco and thalidomide.
Medical science in the USA was absolutely certain that lobotomy improved the patients outcome.
And of course the recent POLIO caused by the vaccines. https://www.newindianexpress.com/nation/2019/oct/23/oral-polio-vaccine-causing-paralysis-in-kids-study-2051670.html

[NomakeWan]

I actually am from this universe not the one you must be from

Alenia not Alinia and it is 100mg at $20 per pill does not even show in AMA FDA look up online other than a mention of it's ingredients.
https://www.drugs.com/international/alenia.html

NOT the cryptosporidia drug

And it has successfully treated 4 persons I know of, one was on Vancomycin before I told him about it.
He stopped treatment his father ordered the Alenia and he no longer has MRSA.
This is one of the benefits of diversity much is known outside of academically accepted US medicine.
In countries other than the USA people of means do not drop dead in the streets, many many options exist to treat untreatable by AMA illness.

SO I suggest you roll up your sleeve and get what the hell ever they want to push next.
Sounds like a plan! It appears the reason I couldn't find this drug was because it's specific to a particular geographic region, and in addition, it is nothing more than a corticosteroid. If you truly believe that a corticosteroid is all that's necessary to eradicate MRSA, well...I would suggest that you publish your findings in The Lancet, because it would turn the entire pharmacological understanding on its head. But I mean, it must work, a dude on the internet pushing anti-aging gurus claimed it cured people, so it must have! Who needs science...


The AMA began with full and absolute knowledge that Doctors being of good character did not have to wash their hands.
It also fully supported tobacco and thalidomide.
Medical science in the USA was absolutely certain that lobotomy improved the patients outcome.
And of course the recent POLIO caused by the vaccines. https://www.newindianexpress.com/nation/2019/oct/23/oral-polio-vaccine-causing-paralysis-in-kids-study-2051670.html
Ignoring the word salad at the top of the post, the great thing about science that laymen tend to ignore is that it's not a fixed point. It evolves as knowledge evolves, as methods evolve, as tools and diagnostics evolve. And as that evolution continues, models that seemed to work are thrown out in favor of models that fit the universe better. That old science is thrown aside in favor of new science does not invalidate science. Science having been wrong before the tools and research existed to prove otherwise does not invalidate science. If anything, it shows that science cares more about getting closer and closer to truth than it does about being right.

But your casual anti-vaccination stance and linking to an Indian newspaper rather than the study it's supposedly quoting from is telling. For one, the "direct quotes" it associates with John only appear in the newspaper itself and internet postings referencing that newspaper article, rather than any study as it claims. That's usually a pretty big red flag all by itself. Also a red flag is that this newspaper post does not quote the title of the study and does not provide the DOI for the study. Further, while it claims that this study was printed in the journal "Indian Journal of Ethical Issues," an attempt to even cross-reference that journal with the purported authors yet again only results in this newspaper article and internet postings referencing this same newspaper article.

For the sake of argument, there was at least an interview with one of the purported authors related to the OPV in India. That interview can be found here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6402912/

Important to note from the interview is that he is not clamoring for an end to vaccines (he suggests that switching to IPV from OPV is the way forward to conclude the eradication of polio), and in fact is very much against folks like yourself who appear to be. Quote:


There have always been self-appointed opponents of anything that is good. In the vaccine arena, there are two types, starting with a few people who genuinely believe that vaccines are unwanted, harmful, and serve only to profit manufacturers. Some of this group have experienced an unfortunate event, like a child dying soon after immunization, and erroneously attribute that event to the vaccine. They seem to be in the minority.

The other type are irrational. Their beliefs do not stem from the cognitive realm and are not easily overcome with factual information. They are vocal and argumentative and try to dissuade parents from immunizing their children. They work on the fear principle. We do have our share of such individuals in India. What we have done through an organization called the Child Health Foundation is to provide high-quality vaccine education for government immunization officers and pediatric academics and practitioners so that, in their own contexts, they become true experts to combat disinformation and misinformation.

And finally, my apologies to the OP. I didn't expect that two months later this user would come back to post these things, but I believe that with this it's become obvious where anyone stands on the issues at hand. The rest I leave up to whoever may stumble upon this thread in future. Peace out.

[daveosx]

Sounds like a plan! It appears the reason I couldn't find this drug was because it's specific to a particular geographic region, and in addition, it is nothing more than a corticosteroid. If you truly believe that a corticosteroid is all that's necessary to eradicate MRSA, well...I would suggest that you publish your findings in The Lancet, because it would turn the entire pharmacological understanding on its head. But I mean, it must work, a dude on the internet pushing anti-aging gurus claimed it cured people, so it must have! Who needs science...


Ignoring the word salad at the top of the post, the great thing about science that laymen tend to ignore is that it's not a fixed point. It evolves as knowledge evolves, as methods evolve, as tools and diagnostics evolve. And as that evolution continues, models that seemed to work are thrown out in favor of models that fit the universe better. That old science is thrown aside in favor of new science does not invalidate science. Science having been wrong before the tools and research existed to prove otherwise does not invalidate science. If anything, it shows that science cares more about getting closer and closer to truth than it does about being right.

But your casual anti-vaccination stance and linking to an Indian newspaper rather than the study it's supposedly quoting from is telling. For one, the "direct quotes" it associates with John only appear in the newspaper itself and internet postings referencing that newspaper article, rather than any study as it claims. That's usually a pretty big red flag all by itself. Also a red flag is that this newspaper post does not quote the title of the study and does not provide the DOI for the study. Further, while it claims that this study was printed in the journal "Indian Journal of Ethical Issues," an attempt to even cross-reference that journal with the purported authors yet again only results in this newspaper article and internet postings referencing this same newspaper article.

For the sake of argument, there was at least an interview with one of the purported authors related to the OPV in India. That interview can be found here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6402912/

Important to note from the interview is that he is not clamoring for an end to vaccines (he suggests that switching to IPV from OPV is the way forward to conclude the eradication of polio), and in fact is very much against folks like yourself who appear to be. Quote:



And finally, my apologies to the OP. I didn't expect that two months later this user would come back to post these things, but I believe that with this it's become obvious where anyone stands on the issues at hand. The rest I leave up to whoever may stumble upon this thread in future. Peace out.


You have again mistaken the drug is in the same class as Leviquin and similar it does function against staff there is an inhaler common in brazil with a similar name but the n ahas a tilda above it.
Like I said you should follow the AMA device until you can't as for me I will live free and happy.