Target idle.

[jameslleary]

Can somebody open up ASDU and see what the Idle is set at? I have done the proceedure a few times for minimum air, but its still not right. I just want to make sure that I am going for the right idle speed. I have seen some posts on the net saying 525 +/-25 in drive, but I cant get it down to the 425 range. I must have the wrong info.
PS-Still have not found an OBD1 tuning App for iPad...I would do it myself if I could.

[gregs78cam]

I think the target idle - 100rpm is only an estimate, just to make sure that the IAC has a little bit of range below target idle. If you can get the idle you want with between 10 and 20 IAC counts you should be fine.

[jameslleary]

Thanks...I have no way to log, all i have is a hand held tach. I know that it needs to be set 100 below target, I just need to know what target is. This is a Factory ASDU prom....not modded.

[EagleMark]

ASDU is 525 stock totally warmed up in closed loop. If you can't get it that low just get it lower then that and stable.

Without looking at data it's a little harder. Drive around and get warmed up, turn off and cross A and B of ALDL plug, turn key on, unplug IAC, start engine and rev to 1500ish RPM for a minute to insure CL timer delay is met and O2 is warm and gone closed loop. Then set idle below 525.

[jameslleary]

Is that the minimum idle air setting, or the actual idle speed in drive(Target)?
Edit: never mind....i got it, thanks Mark!

[Scorp1us]

What is OL timer delay?

[EagleMark]

What is OL timer delay? I made a mistake in that post above and will change it to CL where it says OL. (Closed Loop / Open Loop)

There's several OL and CL delays depending on the bin file. Some bins are OL idle and some are CL idle. So depending on the bin there is a delay going from CL while driving to OL idle. There is always a CL delay when started on these to insure O2 is warm enough.

[black dawg]

Does it have to stay in closed loop to set this min spec? I have never heard of setting the idle 100rpm lower than spec, is this actually needed?

[Scorp1us]

Hrm, yes, getting a vehicle into OL while warm and at a stop would be hard.

BD: yes, it shouldn't be in Open loop at all. in open loop it's not looking at the O2 sensor. But the reason why you set it to 100 less is that the IAC should be closed when you do this. Later when the IAC is partially open, it will be putting more gas in for the air coming from the IAC and will increase the idle speed. Then if you're worried about drive or AC being on, there are "bumps" to the idle for those.

[EagleMark]

Yes it has to be in closed loop for this procedure to work properly because the taget idle speed is set from the "IAC - Desired C/L Idle Speed" table.

It's not an idle setting, it's a minimum air setting. Your trying to get as much air past throttle blades as possible but still let IAC control idle.

Is it needed? Usually no. If your TBI system is stock with less then 125K miles it is probably fine, if you find your throttle sticking and jerks open when you hit the gas, but does not jerk open with engine off, then yes it's needed as the throttle shaft has worn and blades are not open enough. If a conversion to another engine it is usually needed. If your warmed up Closed Loop idle IAC counts are more then about 50 - 60 it is needed.

[black dawg]

OK, it must be lack of closed loop that is giving me problems. I just converted my 91 burb from 350 to 454, and have the 454 throttle body and prom. It goes into CL easy enough when you fast idle it, but falls out almost immediatly when it idles. Probably because of the open manifolds? Hopefully will get the exhaust finished up by the weekend.

[EagleMark]

Could be the open manifolds or BB could very well be an Open Loop idle.

Start a thread for your project and post up the bin and we will try and help.

[jameslleary]

Ok, I have set the min air at 525ish...in that neighborhood anyway. Idle is surging pretty bad. She idles a little high, wont kick down below 800 until put in gear.
When the idle finally gets drops to around 550-600, it surges.
No vac leaks.
Fuel pressure at 13 psi.
No codes.
Brand new Walker stock replacement exhaust, with new Manifolds.
TPS checks out good on the DVOM.
There is a sucking noise, that sounds like its coming from the steering box when it surges. Going to unhook all vacuum operated accessories to see if it clears up.

[jameslleary]

I think my tach might be BSIng me. Seems like 550(per this tach)is too low.

[EagleMark]

Without a scanner or TunerPro software and a cable it's hard to get anything right and know what's going on...

[jameslleary]

yeah...it would be nice if someone wrote a program that would work with the iPad, this would be a nice little tool.

[jameslleary]

Ok, I found that my P/N switch had a bad wire, hanging by one strand. Reset min air early this morning, and it seems better.mJust a little bit of surge, but that might get better after the ecm re learns idle. Also....I fixed my PC laptop! Woohoo!

[jameslleary]

Ok, so here is the first Log on this TBI system. The blm seems low at idle...Could this be part of my problem. This log is a como of in town and freeway driving.

[EagleMark]

Your log is fairly consistent, all rich.

Where are you? What's the elevation?

[jameslleary]

California Central valley, about 120' elevation. I do have an adjustable regulator, should i try these 305 injectors I have in my tool box, maybe at 18 psi. Was looking at my injector spray pattern last night, doesnt look like a fine mist, but its not droplets either. These 305 injectors may be in good shape.

[PJG1173]

I wouldn't be putting the 305 injectors in a 350. just my opinion though. Id change the flow rate in the bin to lean it out a tad.

[EagleMark]

Your way to close now to start another complete project.

[jameslleary]

I wouldn't be putting the 305 injectors in a 350. just my opinion though. Id change the flow rate in the bin to lean it out a tad.
cant tune yet....dont have the chip adaptor for the 7747, nor the balls to make the mod to a flash chip. someday. Since I am running a stock bin, it would be great to get it all into spec just on the factory tune, and get the emissions cert done. Once that is done, i may do the mods, and use Mark's Highway cruise bin, as long as it wont melt my Cat.
Oh yeah, scored a 3M efi cleaner kit at Autozone today, Followed all the steps, will see if it gets better. If not, I will sendnthe injectors someplace to have them done.

[PJG1173]

your other alternative would be to lower the fuel pressure .5 - 1 psi at a time until it leans out enough. when my setup was stock I switched to an AFPR I adjusted for 13 psi and I was globally rich on a stock tune. I had to back down to 11.5 psi to get blms to fall back in line.

[jameslleary]

Ok, so I have my idle BLM at 125 now. ended up cleaning the injectors with a home made tbi injector cleaning machine that I built with an extra injector pod, and an old inline tpi pump I had laying around...ran straight SeaFoam through them. Also, got another Throttle body base from Dave, which had the idle screw plug from the factory....cleaned her up and stuck the injctors on...all seems ok for now, still need more time for the computer to relearn, but very happy so far!
Thanks for your help guys!

[PJG1173]

do you have pics of this home made injector cleaner?

[jameslleary]

I can get some when I get back to da house.All I did was zip tie the injector pod to a piece of wood mounted to the side of a white laundy detergent bucket, fed the pump through a barbed fitting in the bottom of the bucket with a filter inline, and just left the bypass side with a rubber hose dumping into the bucket. used aligator clips on the injectors and used a battery to open them. Really a budget setup, but it worked.
Same thing as using one of the air tank based kits, but you are spraying into the bucket, instead of running the engine on the cleaner....just makes it a little easier to watch the spray pattern.

[jameslleary]

ok, I am still fighting with this, despit a fullm ac delco tune up, including ALL sensors.
The only things not replaced, are the injectors, but they spray a nice cone since the cleaning
New Catylist,so plugged exhaust is out of the question.
Fuel pressure is in spec. Timing is 0*
Grounds couldnt be better.

I have done the Min air adjustment over 50 times. After the idle is set, I fire it back up, and it seems ok while sitting in the drive way.
Move it from the driveway and take it for a spin, and bwammo, the surge is back. Blm still low, except after each time i do the minimum air proceedurs,regardless of what calibration I run. I thought I had the problem solved with the new chip program.
http://i144.photobucket.com/albums/r183/jameslleary/6c1d30ab.mp4

[jim_in_dorris]

Two things James: what is the sound in the video that sounds like a card on bicycle spokes, and have you tried lowering your fuel pressure?

[EagleMark]

Yeah what's that noise?

The surging sounds so much like a vacuum leak, BLM low sounds like vacuum leak, driving good except idle sounds like vacuum leak, have you checked for vacuum leaks?

[jameslleary]

Thats the injectors, and i Think this iPad mic is real sensitive. I have checked for vacuum leaks, both above, and under the manifold.
I do have the injector pod spacer, and the injectors are a little louder since installing it.
I have the stock regulator on it right now, the adjustable one wouldnt go much below 12psi.

[jameslleary]

Seems like the second it gets a vss signal, everythings goes tits up at the next stop.

[jameslleary]

Ready to tear my hair out. Going to pull the intake today and physically confirm no vac leaks. Im glad this is not my old tpi setup.

[EagleMark]

Maybe try no VSS first? Or just disconnect it and let the Error code go... I've never heard of this issue but if you have decent idle until VSS signal it may not be a vacuum leak? Intake manifold gaskets usually don't go bad (unless you use Death Cool) or replaced them with a glitch...

Also never heard injectors make that much noise? Does the spray pattern look OK or drippy? May have the O ring and metal ring in wrong?

[jameslleary]

Hmm...interesting. Ya know, I am using the 86 vss that is on the backside of the cluster. The Optical part itself is mounted behind the speedo, but I have the VSS wire for the ECM connected to the output located at the output that is on a separate box that is wired to the optical unit.
Putting the socket wrench down to consult diagrams again.Spray pattern looks good.

[EagleMark]

That would be the DRAC. Have you ever logged data or used a Scantool to see what the MPH is?

[jameslleary]

Cant go without vss....I have a 700r4.

[jameslleary]

Speedo is about 1 or 2 mph slow, compaired to when logging.
Beginning to think I have an internal mechanical issue, Or, The dealership installed a 305 instead of a 350 back in 2001...the side of the block has 388 cast in the side, and the back deck says 5.7. i dunno what gives.
Heres another video. I did manage to get the flashlight in the right spot for a brief moment. This is a different set of injectors I had installed after the last video...still seem as noisy. Injector spacer, and cfm-tech super sucker have been removed until this problem is solved.

Video: http://i144.photobucket.com/albums/r183/jameslleary/b3b29a93.mp4

[EagleMark]

Cant go without vss....I have a 700r4.To check idle and driveability you can.

What chip are you running with a large cap HEI? Spark latency is differant by as much as 11 degrees between the 2. Both will be 0 with timing wire disconnected, wonder what your connected timing is at idle?

Running EFI wiring next to or touching spark plug wires is a non-no... that must be a conversion?

I wonder if it makes a difference whick side injectors are on since they are both same colors?

Didn't sound near as noisy.

Did we ever look at your data log? 5.7L injectors in a 5.0L would cause issues? Wish I could be more help...

[jameslleary]

To check idle and driveability you can.

What chip are you running with a large cap HEI? Spark latency is differant by as much as 11 degrees between the 2. Both will be 0 with timing wire disconnected, wonder what your connected timing is at idle?

Running EFI wiring next to or touching spark plug wires is a non-no... that must be a conversion?

I wonder if it makes a difference whick side injectors are on since they are both same colors?

Didn't sound near as noisy.

Did we ever look at your data log? 5.7L injectors in a 5.0L would cause issues? Wish I could be more help...
I am running ARJU.
The large cap HEI is an Early TPI corvette Dizzy, which also was on the original CCC system that the truck came with from the factory.
Yes, it is a conversion from SD TPI.
Yes I posted a rich log, BLM constantly in the neighborhood of 115.
I had Idle problems with TPI too, and through the tuning process, I wiped out the required dual Cats...which was the last straw, and helped push the decision to Step back to TBI.
Just cant catch a break, It seems like this engine was doomed from the get go.
I know I dont have any head issues, it has new 193 heads.
I do have a comp 12-388-4 cam, which was suggested to me by S&P for the TPI, but is also listed as ok for TBI.
At the point now where I am sorry I even got rid of the CCC setup....been keeping my ear to the ground for a harness and carb to put it back the way it was. I Love EFI, but with the money I have thrown at this, trying to figure out the crappy driveability issues, I could have a new GM Crate Engine.
The injector plugs have been replaced, the moron that I got the harness from, cut the originals off. The green and white wires are going to the drivers side, per all of the virgin TBI trucks I have seen.
I have tried to switch them, and i do notice rougher running.
Might throw the 5.0 injectors in there, just to see what happens.

[EagleMark]

That really sucks! Now if you had issues with TPI and now TBI, what was the same in both? Looks like a nice Suburban, mine has been great with TBI from factory, never an issue, more of a test bed... and family rig.

Can you put a vacuum gauge on it at idle? What is it reading? Steady?

[jameslleary]

Yeah, Its a nice truck.
At this point, I just wish I never swapped out the CC Qjet.
Vacuum is rock solid in park at 19, and in drive at 17..... until it starts surging.
The issue was mostly idle on the tpi, and getting it tuned right for the truck so it wouldnt detonate.
The successful people (Person, Fast305)on the boards are not to quick to help out or answer questions, I am glad thise forum started up.
TBI is just Idle problems.
As far as the Minimum Air proceedure, there ar so many different versions out there. On even says to pull the est, and put it in drive to set.
I want to know what they do at the factory. I have stopped adjusting the TPS to .54...they dont do it at GM, and I shouldnt have to do it just to get it to run right.
I have seen some tps voltages as high as .71, and the truck runs like a Cadillac.
And it has a bad effect on my WOT voltage.

[EagleMark]

What about charging voltage at idle? Is it steady or declining? Declining is a common issue in conversions as they draw more juice with less altenator.

I've never had an issue with TPS voltage over .54 up to .80 but have been tols at 1.0 volt it is an issue.

Factory did not do min air. TBI was new and set. When they wear or get rebuilt or used on foriegn engine they need to be done. I have my own way that takes into account all the things you have read, but bottom line is an IAC count of 20 to 40 CL warmed up idle.

Check your timing with a dailback light and see where it is at idle. I'm really thinking the large cap HEI if running a small cap EFI chip could be way off.

[jameslleary]

Ok, I will check the timing with my snap on advance light tomorrow. I think you may be on to something with the distributor. My distributor is the only thing that is different about my conversion, vs the 40 something other conversions that I have done, which have been totally trouble free.
So for now, could I set the idle using The idle counts on the TPRT dash, and set it so the idle counts are 20....seeing as this engine seems to run better with the blades open farther?

[EagleMark]

I think you may be on to something with the distributor. My distributor is the only thing that is different about my conversion, vs the 40 something other conversions that I have done, which have been totally trouble free.
And there's your sign!



So for now, could I set the idle using The idle counts on the TPRT dash, and set it so the idle counts are 20....seeing as this engine seems to run better with the blades open farther?I to think they run better open further but have to leave a little left for IAC to control idle. I really like to do this totoally warmed up and driven a little, then idle and look at IAC counts, if 20ish then good. If high then open up blades 1/4 to 1/2 turn and turn engine off for 30 seconds, restart at idle then rev engine for 30 seconds, goes CL and let idle, check IAC counts.

[jameslleary]

ok, the timing is at 14* both in drive, and park. I believe tho SA table shows 26.02 while idling, shouldnt it match up?

[PJG1173]

ok, the timing is at 14* both in drive, and park. I believe tho SA table shows 26.02 while idling, shouldnt it match up?

are you verifying this with a timing light or tunerpro? if tuner pro do you have the base timing accounted for in the adx?

[jameslleary]

are you verifying this with a timing light or tunerpro? if tuner pro do you have the base timing accounted for in the adx?Its a stock, untouched bin. Base is set at 0*, 14* with the EST connected, Using a Timing Light.

[EagleMark]

It depends on the bin and warm spark bias which is usually 9.86 degrees for SBC 7747, where BBC 7747 warm spark bias is 0. So you are only off by 2 degrees and that is probably to do with Spark Latentcy Correction which is not accurate in a stock bin... I don't think that is your issue but you could try and add 5 degrees timing at idle to see if it helps? If it does then changes are needed in bin before any WOT high RPM driving.

You've got good high vacuum and don't sound to be a newb at this...does MAP in TunerPro convert to same high vacuum? Wondering if there is a leak or faulty MAP sensor? If you can't find any vacuum leaks maybe pull and read plugs, you will find one or two off if you have a vacuum leak under intake...

[jameslleary]

Ok, going to run to the store, then I will compare the TP MAP to my vac gauge...funny, was just thinking this in the shower, of all places!

[jameslleary]

Base timing is now set at 5*
both logs were taken when i got back from the store.
1st log, 619idle, is where she is pretty happy, no surging, but 0 idle counts.
2nd Log, 619idle2, i backed off the idle screw to get the iac to open up. i aimed for 20 counts, but got closer to 40 at restart. Surges Pretty bad
MAP is spot on with the vacuum gauge.
I am a newbee at tuning. Before, I just did wiring and installed EFI components in place of Old School Carb systems. This tuning stuff is all Greek to me.

[EagleMark]

Must turn off engine to reset TPS to 0 % when restart. Or just disconnect battry to clear learn and see where she ends up. Second one was not that bad for IAC counts considering the idle variation

[jameslleary]

Must turn off engine to reset TPS to 0 % when restart. Or just disconnect battry to clear learn and see where she ends up. Second one was not that bad for IAC counts considering the idle variationThe engine was shut down between those 2 logs.
Can you see the idle surging, or is the Data kinda jumpy there too. Some cases, it got way down below 500 in drive.
I wish I had a temp gun, The temp sensor seems to be reading a little cool.

[jameslleary]

Notice that Rich BLM too?Is there anything that could occure in the ECM to cause the rich condition? I have literally gone over the engine over 50 times looking for faults. 5 of those with all the vacuum accessories plugged off.

[jameslleary]

Just went out and fired it up and watched it through TP. BLMs Perfect at 128, o2 voltage eventually climbed to over 700, and the engine ran smooooth, at 800.
Then it went into CL, o2 voltage shot down to the 3 to mid 400's, and the idle went to hell.

[EagleMark]

So it was idleing smooth in OL and went CL and went to hell? Hmm... the O2 readings you are seeing are cross counts, supposed to be there.

Have you read the plugs on O2 sensor side yet?

[jameslleary]

Yeah, thats one of the first things I did. They did look a little on the rich side.

[jameslleary]

Going to pull,the drivers side manifold and inspect it, Low o2 voltage after going into closed loop makes me think air is getting in there somehow. I do have a little tick under accelleration.

[jameslleary]

Well, thats it. I cant think of aything else that could cause this. I know the engine has the ability to run right, because its a dream in OL, BLM and INT are both at 128.
I did notice that the o2 sensor seemed to stall out for quite a long time...the voltage did not change for about 30 seconds...so the sensor will be replaced soon.
Injectors will be sent out for a professional cleaning.
Maybe the after market cam? I dunno. Maybe pull the wiring harness back out and go through it again.

[PJG1173]

Well, thats it. I cant think of aything else that could cause this. I know the engine has the ability to run right, because its a dream in OL, BLM and INT are both at 128.
I did notice that the o2 sensor seemed tom stall out for quite a long time...the voltage did not change for about 30 seconds...so the sensor will be replaced soon.
Injectors will be sent out for a professional cleaning.
Maybe the after market cam? I dunno. Maybe pull the wiring harness back out and go through it again.

I have an aftermarket cam and headers and my NB o2 voltages at idle are 750-800mv OL but my WB reads 14.7 -15ish. if I enable CL idle goes down the crapper too.

[jameslleary]

i dunno if I can get away with an OL program on this with smog. They do it with 454's i think.
I need to figure this thing out before November, when I have to go to the referee to get certified.

[jameslleary]

Staring at my engine late yesterday to see if there is any other possible spot for a vacuum leak, checked the block off plugs to see if they are loose...nada.
Then After a lot of mind bending thought, I began to ponder the vacuum leak that is there on purpose...the pcv valve.
Even though it is a metered leak, it is a leak period. But I did not replace the valve when I did the swap(either swap, not even TPI) With a TBI specific valve. I am thinking, and hoping, that this valve, probably for the CCC setup, is the culprit...and for under $5 for the TBI specific part, its worth a try!

[EagleMark]

I've never compared them but wish you would look at at least opening hole on bottom, I have seen different sizes but don't know apllications.

[PJG1173]

I recently replaced mine because I could actually hear it sucking air while in the valve cover and my idle dropped a few rpm's.

[jameslleary]

I've never compared them but wish you would look at at least opening hole on bottom, I have seen different sizes but don't know apllications.Will do!

[jameslleary]

Ok, well that was not it. Old and new valve are the same part number, but the spring inside the old valve was worn out pretty bad.
Oh well.
Now I am really stumped, I have no idea where fresh air could be getting to the O2 sensor, next step is to replace it i guess. i will be sending my injectors off tomorrow or Monday.

[jameslleary]

Whoa...Hold the phone here.
Before I do anything else, here is another thought.
Could I be possibly using a bin that wants to see the o2 sensor in the Y pipe, or maybe the ecm wants it there?
How can I tell? What would i be looking for in the bin?
here is why I ask.
o2 voltage constantly low(lean)in closed loop, BLM constantly rich 111 to 115....seen it as low as 108.
Runs great in OL when it is ignoring the sensors and the o2 is reading in the neighborhood of 700+\-...BLM and Int at 128.
Am I making sense?
Reaching for anything at this point. No vac leaks. no exhaust leaks.

[EagleMark]

I really don't know of any GM vehicles with O2 in Y pipe... been so long trying to help you with this I forget if we ever looked at your bin? What bin? What ECM? Post it up...

[jameslleary]

running ARJU for about the last month, downloaded from this site
7747 ecm.

[jim_in_dorris]

James, just a thought. Have you changed the O2 sensor? If it's lazy, that might be the problem. It sounds like the O2 thinks the truck is lean, and ordering the BLM's rich. Can you look at exhaust with a 5 gas? or have access to a Wide band? What are your short term fueling (INT) numbers?

[EagleMark]

Try this.

[jameslleary]

Hi Jim,
That is what I was going to do today when the stores open up here.
All I have is TPRT, no access to anything else.
Some of the RV Trucks after 88 or 89 had provisions for o2 sensors in the Y Pipe, And after they changed to the 7427 ECM in mid 93 when the trucks started using the 4l60, they all had HEGO's in the Y pipe

Mark,
Thanks, I will give that a go!

[EagleMark]

Following Jims line of thought I wonder if there's a bad ground to O2 sensor?

Thanks for clearing the Y pipe O2 up for me. Were they all heated back there? I know lots of truck 7747 were OL idle...

[jameslleary]

Yes, they were 3 wire.
02 ground from ecm is good. Its bolted to the Passenger side head, right on the same bolt that the battery ground is bolted to.

[jameslleary]

Well,
Thanks for the help guys. This truck has consumed me for quite a while.
Today I replaced the o2 sensor...o2 voltage swing isnallot better.
Was spraying around the intake for the heck of it, and cought a vac leak inside the egr, on the valve shaft its self. Replaced valve.
I also have a black check valve on my brake booster vac line that I was repositioning, and thought I heard an air leak from it. The silver ring around its seam was loose. I twisted it, and it felt like it tightened up, and my brakes seem more responsive.
The power is a little better, but it does not want to idle at factory specs...at least not with the IAC contorlling it.
Going to send the Injectors to MR Injector this week. After that, and trying the BIN that Mark posted, I am throwing in the towel for a while.

[EagleMark]

I'm about ready to come to CA and fix this dam thing! :rockon:

Actually I don't know if I could do more then you have but glad you found a couple issues today! That would be enough to mess it up you know! Only thing left is cleaned injectors and getting min air set right.

I forgot you had large cap hei, I will post another bin with proper spark latency for that if you want? I guarentee that bin will work, even without. I just wanted to see if your bin had an issue...

[jameslleary]

Thanks Mark I appreciate any help I can get, I just want it to run right stock, so I can start to learn about tuning....I know very littlel about the nitty gritty.
Just came back in from playing in the dark,,and found out that when I rev it, base timing, esc unplugged, moves 1*...oh joy. l have decided that I am going to pull the harness out for inspection, and final cleanup. The harness is from a GMT400 truck, which is the next body style after the 73-87(to 91 for HD, Blazers, And Burbs). so it isnquite a bit longer than what is meant for my application. After seeing that thread with the 60s Suburbans, I think I might mount my esc and MAP under my dashboard. I really like the clean look.

[EagleMark]

One degree is nothing, probably timing chain or distributor slop.

Really don't think harness needs an overhaul, although I would look at spark plugs wires or EFI harness to close to distributor. If it's for asteics then that is your decision.

Bin file is very close to stock, Hiway Lean Cruise, Smoother spark table, all it needs to be accurate for your motor is spark Latency correction for large cap HEI. It's the base for ever 7747 I tune, actually it's the bin from my Suburban which has the ECM permanantly hanging on floor so I can test ECMs and chips, it's my biggest test bench! :laugh:

[jameslleary]

Main reason for going through the harness, is that it is too long, and snakes around behind my dash....and I may find part of my problem. Just a clean up and confirmation that everything is right.
Your at a much higher altitude than I am, Will my using that bin cause any problems? Are you running a Cat?

[EagleMark]

2000 feet, same bin for all states, yes I have a cat on the Suburban, but I like my dog much more! :rockon:

It was just a shot to see if you had an issue, your welcome to it if you wish. My Suburban runs good from sea level to 6500 feet! Don't think I've ever been higher...

[jameslleary]

Cool, I will definately try it. Thanks
I will post back here periodically, with the hopes of finding the problem, and so anybody with a similar problem will find this thread in the future

[EagleMark]

Don't be a stranger!

Your one of us now, come back and share! :thumbsup:

[jameslleary]

Ok...did the intake gaskets. No change. Running the highway mode bin, no change at idle, still have yet to take it out on the road.
One more thing that I thought i replaced but didnt, is the MAP sensor.
MAP and Injector cleaning are going to have to wait for $$$ to come in.
I also need to pull my timing cover, and check and replace my timing chain, and I may throw a stock cam back in...or one close to it. I have heard good things about the Melling MTC-1.
If those dont work, I am thinking LS 6.0 swap, or the 87-95 GM replacement engine.

[EagleMark]

Ah dude your breaking my heart here!

Didn't you say you got 19 inches of vacuum at idle? If so and no jitters it's not a cam issue. At this point I would not talk you out of a MAP, espeacilly if it's the same one from the other motor. But I would put a Small Cap Distributor in long ago, first... speaking of which here is the same bin with spark latency values for Large cap HEI. If it works I'm gonna die....

[jameslleary]

Oh cool! I thought the bin you posted the other day had the correction. I will definately try it tomorrow. The MAP is the same one I was running with the TPI setup.
I am really baffled with this. my vacuum is usually in the 17-18 range at idle.
When I stick it in drive, itseems like it settles at 600 rpm or so, and then tanks all the way down to 525, and thats where the surging starts, clear down to 450. it even does it with the IAC unplugged while trying to set minimum idle.
And naturally, the vacuum moves with the surge.

[EagleMark]

Hmmmm... that vacuum should be fine anywhere, your sea level right?

Here's the same bin with "IAC - Desired C/L Idle Speed" increased across board to 625, stock it will go as low as 525 so maybe with your slight cam we just fixed it?

It will still idle higher when cold or in neutral.

[jameslleary]

Cool, thanks. 625 seems like a happy speed for this engine. So, another min idle air setting to 525 for this bin?
Two different schools of thought on whether or not the vehicle should be in gear during Min Idle adj...some are even saying to pull the est pigtail.

[EagleMark]

Never heard pulling EST pigtail? You mean timing disconnect wire? That would be a bad idea to try and set min air at 0 timing, then add 15 degrees? I don't think so...

Just give the bin a shot, when totally warmed up and driven then let it idle and see where the IAC counts are. 20 to 40 your done. 0 and you got to close the throttle plates, over 40 got to open them. There's the GM set procedure of crossing A and B of ALDL to drive IAC closed, discconnect IAC, start engine and set to 100 RPM below desired CL idle, reconnect IAC then the problem is you have to claer codes and you loose your BLM learn, so you don't know if you got it right till you drive a half hour?. I've found it easier to close or open 1/4 turn, turn engine off for 30 seconds, start let idle, rev engine to like 1500 for 30 seconds and check IAC counts for next minute. Way quicker.

Have you checked and or replaced the vacuum line from back of TBI to MAP? Thick vacuum line, or the stock hard line that will not collapse!

[jameslleary]

Never heard pulling EST pigtail? You mean timing disconnect wire? That would be a bad idea to try and set min air at 0 timing, then add 15 degrees? I don't think so...

Just give the bin a shot, when totally warmed up and driven then let it idle and see where the IAC counts are. 20 to 40 your done. 0 and you got to close the throttle plates, over 40 got to open them. There's the GM set procedure of crossing A and B of ALDL to drive IAC closed, discconnect IAC, start engine and set to 100 RPM below desired CL idle, reconnect IAC then the problem is you have to claer codes and you loose your BLM learn, so you don't know if you got it right till you drive a half hour?. I've found it easier to close or open 1/4 turn, turn engine off for 30 seconds, start let idle, rev engine to like 1500 for 30 seconds and check IAC counts for next minute. Way quicker.

Have you checked and or replaced the vacuum line from back of TBI to MAP? Thick vacuum line, or the stock hard line that will not collapse! yep, I have a piece of small diameter efi fuel line on the MAP.
For the 20 years that I have been doing swaps, I have always used the ALDL a and b jumper method to set idle when in gear, like GM states in the TSB they sent out in 87-88 for bottoming out IAC valves.
I was just trying to get your thoughts on the other methods.
Burning the new ASDU you sent, hen going to give it a whirl!

[jameslleary]

Mark, did you disable the IAC? mine is staying shut, not taking commands.

[EagleMark]

I wouldn't even know how?

[jameslleary]

Crapola.
Gonna try your unmodifed bin and see if I get it back

[EagleMark]

I just did a compare and can't find any reason for it? Bin is not corrupt... here.... CEL come on and flash when key on?

[jameslleary]

Ok, i dont know what I did, but the IAC is back. The problems may be in this harness. This Bin does run better, though!

[jameslleary]

We posted at the same time. Yep, the light came on...but now I have IAC back after messing with the throttle blad stop screw.
Just looking at my throttle blades...one looks bent! A bunch of George Carlin cuss words come to mind. good thing I have 2 spare sets of throttle blades!
I know, i Know....one thing after another!

[EagleMark]

One of these days we'll figure it out.... I hope.... having intermittent IAC, I could see where that would cause idle issues!

[jameslleary]

One of these days we'll figure it out.... I hope.... having intermittent IAC, I could see where that would cause idle issues!I think it may have been a mistake by me, because of the throttle plate issue. I did notice, that fuel was puddling a little at the back of the Drivers side plate....WTF? Swapped sides with the injectors....same thing, still on the drivers side. Cracked it open a tad, stoped puddling, but this also opened the passenger side more. Looks like the someone may have tried to force it shut when the stop screw was turned all the way out...may have twisted the shaft.. I make a point on never letting the blades bind in the bore. I never let the tops of the blades close beyond level with the bottom of the vacuum ports, which is by the way, How I have seen every factory capped TBI set.

[PJG1173]

after having my TB bored I had fuel puddling on one side of the TB. It just means the blades are not centered in the bore. mine is out at the machine shop getting new blades made. This could be because the hole the butterfly shaft goes through is egged out from the throttle return spring on the driver side. might want to check it for play.

[jameslleary]

after having my TB bored I had fuel puddling on one side of the TB. It just means the blades are not centered in the bore. mine is out at the machine shop getting new blades made. This could be because the hole the butterfly shaft goes through is egged out from the throttle return spring on the driver side. might want to check it for play.just had new bushings installed last month. Gotta take it apart anyways, will check, thanks!

[jameslleary]

Woohoo! Progress!
Just went out and drove around for a bit...98% better. There is an extremely light surge, But I think that may pass as the computer re learns. but it is definately more tolerable.
Befor I took it out, i fixed the throttle blade difference, and that, along with Marks distributor adjustment in the bin, have this baby running alot better.
Mark, What speed does the Highway mode kick in?

[EagleMark]

You can look at it all in the $42 XDF in a catagory Hiway Lean Cruise. It is set up for me! I do a lot of 40 to 50 MPH long back roads around here so its set to start the timer of 40 seconds at 40 MPH. You may need something differant like if all you do is 70 on freeway, 40 seconds after 60 MPH.

If MAP gets a load of 74.69 it kicks out.

[jameslleary]

Ok, will take a gander. I am In the middle of Ca farm land, so a lot of my driving is over 50mph, so the way it is set, should be perfect. What I need to do now, for when smog time comes, is find a diverter valve for the air system, and hook that up. Im not going to try and attempt passing without it. I also need to compair the federal, and CA bins, to see if there are any differences that will doom me at the sniffer.

Far future:
If I dont get the money for an LS conversion in a few years, I want to develope an MPFI, using a dual plane manifold, with a divorced EGR setup, and maybe try to get it by on Edelbrock's EO number...that way, i dont have to change to dual cats.
Unless of course, I can find a screamin deal on edelbrock's old 3501 manifold.

[EagleMark]

Your Suburban needs an Air Pump in CA? Guess 86 did but 87 did not in the real world with TBI. May be easier to pass with 87 motor?

I only lived there a short time when unemployment was high in AZ, hated the smog nazis! Then went to work for a company and had to learn all the ins and outs for conversions and transplants for years and still hated the smog nazis!

[jameslleary]

Your Suburban needs an Air Pump in CA? Guess 86 did but 87 did not in the real world with TBI. May be easier to pass with 87 motor?

I only lived there a short time when unemployment was high in AZ, hated the smog nazis! Then went to work for a company and had to learn all the ins and outs for conversions and transplants for years and still hated the smog nazis!
Well, the problem I have in CA is; Some 87 to 93 trucks did come with AIR, and some didnt. No way to differentiate betwix them. I did, however, find Vac diagrams on Autozone.com for Ca trucks without the pump. If I am going to try to pass without, I need to bebsure that I have a bin that wont try to command a shot of AIR into the manifolds, and trigger a CEL when the o2 sensor does not see it.

[EagleMark]

You got one right now.

[jameslleary]

Shweeeet! Im gunna have to start calling you Santa!

[EagleMark]

Just cut my white beard off and shaved head for summer... :laugh:

[jameslleary]

Ummm.. Mark?
My trans is locking up at 10 mph in second gear. How do I fix that?

[EagleMark]

Hammer?

The tourqe converter? Hmm.. never took that into account, this was supposed to be a test, is it 700R4? 1986 had CCC right, so there is the origanal DRAC and VSS? Are you data logs speed close?

[jameslleary]

Yes 86 VSS at the speedo, same 700r4 as yours, didnt even bother with the original 86 trans.
was used to a 30 mph lockup for 3rd, and a 38 lockup in 4th. I have 31" tires, and 3.42 gears.

[jameslleary]

Never mind....its not doing it now. But it was wierd when I went to run an errand last night. I would get to around 10 mph, and the TC would lock in 2nd.
GREMLINS!

[jameslleary]

Ok. i think I may have found the problem. Is ecm pin A7 for tcc control a switched ground?

[EagleMark]

GREMLINS! EFI wires near spark?

So it it at least idleing still?

[EagleMark]

Ok. i think I may have found the problem. Is ecm pin A7 for tcc control a switched ground?

http://www.gearhead-efi.com/Fuel-Injection/attachment.php?attachmentid=1937&d=1331599707

[jameslleary]

No, those are separated more, they were not that close really. It is running, with a tiny surge, but like I said, that may smooth out with more relearn time. I found a wire that is Y'ed off from A7, that had some exposed wire...was hiding the harness, and must have com out while doing all this figiting with chips.

[jameslleary]

http://www.gearhead-efi.com/Fuel-Injection/attachment.php?attachmentid=1937&d=1331599707Bingo!
An unused wire Supposed to go to "F" branched off from A7 was making contact with the ECM Case........I wonder what else I missed with this EBay harness. Time to pull and go through it again!

[jameslleary]

ok...here is a log from idleing in the driveway. Still rich.

[EagleMark]

Well it's a wet intake manifold, so to tune idle it has to be totally warmed up and driven or given a WOT pull, then data log. Also BLM were 108 till hit 190 degrees and raised to 110 so your close but that cam is idling at 14 to 15 inches vacuum so yes you'll need to pull some fuel at idle.

Here's the same bin with some fuel pulled at idle and the rest of the VE1 smoothed out for a good starting point. Ve2 is 0ed out so only be working with 1 fuel table. Also all things turned off for data logging. Totally warmed up, go for drive, disconnect power to ECM, start vehicle, rev to 1500 for 30 seconds, let idle till closed loop start data log and do some all around driving.

[jameslleary]

Thanks Mark!
I will have to continue the testing on Monday. Headed up to Humboldt county for a Dog show, will be back late sunday

[EagleMark]

When I lived there they grew something else in Hombolt county... :laugh:

What kind of dog? I've got a Basset Hound, show winner we adopted, best/smartest dog I've ever had FREE!

[jameslleary]

My Father in Law breeds Cardigan Welsh Corgis. We have 3 in the Ferndale dog show on Friday, Saturday, and Sunday.

[jameslleary]

Ahhh, yes...Im not into that Ganja crap. I do like the fact that there are no smog checks!

[jameslleary]

Ok....here is a log done this morning, with some warm up time in the driveway, some backroad and freeway driving, and some in gear, and park idle at the end.

Idle still shakes the front seats pretty good, but the actual surging is waaaayyyy better....almost gone.

[EagleMark]

Dam that runs pretty good! Little rich, more so at idle. I didn't see lean cruise come in? But I didn't look to hard at it either.

Since that cam seems to be lowering vacuum a little at idle I would add a couple degrees spark to idle since that seems to be an issue. Also no signs of knock so I'd add a degree spark to drivable area of spark table and loose just a little VE that dictates it in BLM history. I'm bored I already did it if you want to look...

[jameslleary]

Ok, Thanks Mark!
2 questions.
Did you add spark across the whole board, or just certain cells?
and, at any time are the BLMs supposed to go below 120?
I had no idea that this cam would be so problematic. Makes me wish I didnt swap from TPI, if the cam was really the issue.

[jameslleary]

Ok, I have to have something wrong with this engine, but all the tests say I dont.
BLM`s and Integrator shot way up quite a few times on this log. Its still Idling like a MAF car with a bad vacuum leak.
I really thought I was simplifying things when I swapped Tbi in...LOL!

[jameslleary]

This log didnt post for some reason...here it is. And a video too. Feels alot worse than it looks.
http://i144.photobucket.com/albums/r183/jameslleary/d76f4b03.mp4

[EagleMark]

Is this the same engine that had the problematic TPI?

The cam is not all that bad, great vacuum, just differant.

The log started off fantastic, rock solid idle, perfect BLM, got great vacuum/MAP.. then you put it in gear and it went rich but not all that terrible during the drive, couple spikes on BLM/INT but once was a stall or you lost connection and one was in an area I think is a glitch? Unless you can rev to 5200 RPM without hitting 3200, 3600, 4000 and 4000 RPM? I'm pretty sure that was a glitch, if there were more I would worry but log is consistent.

But idle suffered bad?

Didn't we have the idle way better? When, what, why, happened?

Oops... :homer: somewhere we lost the rasied idle and large cap spark latency! I was watching your log and when you put it in gear idle went down low and IAC went to 0 then the surging, so yeah it'll surge with no IAC to control idle that low and you had adjusted throttle blades for the higher idle.

I just did a Differance/compare with this bin to my bin, only changes are Idle, Spark Latency, Spark advance and VE1 Fuel. Exactly what we have changed and all the right stuff.

To answer your spark question I added 2 degrees to idle because of your idle issues, we may not need now that the idle is back to where it was working better and spark latency was correct. I also added 1 degree to driving range in cruise and acceleration, nothing in decel or low RPM/High MAP. May not look exact if you compare because this time I smoothed it as I thought we were close to done. I watched the spark advance in ADX because the hack is installed in bin and it all looks well within safe zone. Knock had a few counts somewhere but so few it's not an issue. 39 total is nothing and I'd have to watch the whole log again to find something not worth looking for. Lets see what next log does?

[jameslleary]

Hahaha! Ok....I started thinking of a mechanical problem, because the last few bins you tweeked were getting better.
Here is a laugh for ya...after I made that video, the hot water line blew in the bathroom, and flooded the floor with about 6 gallons of water, before I caught it! Spent the last hour cleaning up that mess, and fixing the leak...LMAO!
Can this day get any better?!
Thanks!

[jameslleary]

Oh yes, i meant to ask.
Do you need 70 mph on the logs, or is 55 ok?

[EagleMark]

I hate when that happens! Specially with this truck driving you nuts...

Yeah sorry I don't usually loose track as every new bin gets a new name or number incement, but you saw huge improvement when we set spark latency and raised idle by only 75 RPM with no tuning! Then we went to crap again... I really didn't want to add to your frustration on this, it's actually very close and even idled better a couple bins ago... :homer:

[jameslleary]

You didnt add to my frustration at all, was thinking about looking for a Cadillac engine though! LOL!
Idle still choppy...going to look at the plugs again, but the rpm is back to the 600`s. Very good power, low knock counts!

[EagleMark]

You didnt add to my frustration at all, was thinking about looking for a Cadillac engine though! LOL!
Idle still choppy...going to look at the plugs again, but the rpm is back to the 600`s. Very good power, low knock counts! :jfj: I don't tune Cadilacs!

For a guy who revs to 5575 RPM and only has 26 knock counts I'd say your OK!

Did'nt look to be surging though right? IAC at end of log there at idle RPM was only 16 counts, now I only ever say 78 counts, can you record data and turn key on, off etc and see if they ever go up to 145, or a scantool? With all this idle issues I looked at them quite a bit and other logs and seems you never go high like others at higher RPM indicating something may be wrong on IAC? Double check wiring to the four prongs etc... attached is IAC diagnostic. If all is well I would turn that screw in 1/4 turn with key off.

Took a bunch of fuel out trying to get these BLM in order, used key points and built a new VE table, try it, if idle still the same we may have over shot timing there, if fuel is closer we may need to take that 2 degrees back out at idle. Also this log should produce some higher then 128 BLM which we have never seen! If not you do have an issue...

Log really looked good! Would 25 more RPM at idle help without causing an issue with the auto trans? Is that the only issue, choppy, like rough? I didn't see surge in this log.

[EagleMark]

Just in case you have time and I don't here's same bin with 25 more RPM at idle and the 2 degrees out.

[jameslleary]

Thanks! will try those in the morning.
Kinda hard to explain the idle...
Kinda like a 4 cylinder Diesel, real rough. I am trying to get as close as I can to idling like from the factory. The TBI trucks and Roadmasters always had a cadillac smooth idle, mine is choppy enough to shake my high back bucket seats.
My 6hp briggs and stratton on my lawn mower is smoother.

[EagleMark]

That's got to be annoying! Mine is smooooooth... I can feel and AC kick on and off is about it...

[jameslleary]

It is really irritating. it runs pretty smooth in OL.
The engine started life as a Goodwrench replacement for 86 trucks, which was a one piece main, 2 bolt block, with the parimeter valve cover bolt heads. Ran rough then too, but I thought the E4ME and C3 ecm was the problem.
Installed the TPI one year later...power was awsome, choppy idle
Installed TBI heads, and the new cam in Feb. 09...same Idle
TBI fuel system installed last october...same crap.
In researching the problem, I read in a few places where a few guys got some bad GM "Hecho en Mexico" Crate engines....citing mis matched pistons, sub par machining...the list goes on. That just gave me mor grey hair.
Old lady around the corner has an 87 Caprice, police package, E4ME 5.7...SmoothER than a new LS engine, as smooth as a Northstar...enough to consider suicide.

[EagleMark]

And a mechanical vacuum gauge is smooth?

Have you done a compression test?


enough to consider suicide. You probably wouldn't want to drive this then...
http://www.gearhead-efi.com/Fuel-Injection/showthread.php?998-Mid-Life-Crisis

[jameslleary]

Too late brother...I had one. Black, T tops, bought it brand new in 01. Compression test says 180+ in each cylinder after 7 seconds of cranking.

[EagleMark]

With the vacuum and compression that good, and after all you've been through, I'd still put a small cap distributor in it before I shot it... is it the same distributor as the TPI?

[jameslleary]

Yep, I used the Big cap on the tpi too. I thought it was ok, because it was the same distributor used on the 85 L98 TPI.
Dont have money right now for it, and not alot of wrecking yards out here have that kind of inventory anymore.

[EagleMark]

Yeah it works, but it's one of the few parts that were on both systems with idle issues. With good compression test and solid engine vacuum a questionable engine build still does not make sense? Even if cam timing was off, tests still show good to go.

I'm all for diagnosing parts before replacing but sometimes you can't find the issue. Look at some GM test procedures and pretty simple, then replace part... only way to test ignition beyond basics is an Osiliscope, it'll show all 8 sparks and point out an issue real quick. Watching ignition on an Osiliscope was fairly common practice for tune ups in old days...

The only data from your truck that is off from mine is coolant temp gets to 202F at end of log when you do the idle logging. But that is only 10-15 degrees hotter?

[jameslleary]

I think the only reason the temp got that high, is because i buzzed it up over 5k.
I did have a small cap dist here a few months ago. I did notice that there is no up and down play in it, compaired to my large cap. I had the coil, and the harness to run it too...Dang it!
I ended up Donating my entire TPI setup, along with the small dizzy to a Buddy on the GMSB forum, who is also a Friend of Robert Issar's down in Austin. Everything ended up getting stolen from his garage when his step son left the door open.

[jameslleary]

Here is a log with Bin 6.
Surging is barely noticeable...almost completely gone.
Took the plugs out and cleaned them before start up, didnt look too bad.
Idle counts at 0, probably because I gave it a turn before starting.
Idle still a bit choppy.
But, is the blm supposed to go below 119 at all?
May just send in the injectors next week.
GETTING BETTER!

[jameslleary]

And here is the result of re setting the Min Idle Air again.
I do notice much more power, under less throttle.

[EagleMark]

Did you try 7?

[jameslleary]

Not yet....the idle is just a little higher, and less 2 degrees right?
I have it loaded onto another chip, will go back out after my daughter wakes up.
Is there a possiblity that the lower idle could be used, once all this other stuff is ironed out?

[EagleMark]

Have you watched for a drippy injector? That whole log was dam near perfect, I think I'd add a little more fuel, it did go lean as I expected but just to about perfect.

Except at idle! BLM will be exactly as expected from rest of log then bottom out at 108, then back to where should be. Have you watched for a drippy injector?

Not a single knock count.

[EagleMark]

Not yet....the idle is just a little higher, right?Yes, I added 25 more RPM on 6.

[jameslleary]

Ok...i was adding to my last post when you answered.

[jameslleary]

Have you watched for a drippy injector? That whole log was dam near perfect, I think I'd add a little more fuel, it did go lean as I expected but just to about perfect.

Except at idle! BLM will be exactly as expected from rest of log then bottom out at 108, then back to where should be. Have you watched for a drippy injector?

Not a single knock count.
thats a trip, isnt it!? I think i only got one knock count in the entire 2nd log.
I dont really notice a drip, but fuel does kinda "beed" down the walls of the barrels...I dont remember what a perfect TBI cone looks like in person....but no droplets.

[jameslleary]

Here is a video of my injectors. It was idling really nice in drive when I just did this, maybe it was still in OL...so we know the engine is capable of doing what I want it to.
Note: the plug wires are routed below the harness, behind the valve cover, and the wires have no loom on them until all the bugs are worked out, and the harness gets trimmed to its final length.

http://i144.photobucket.com/albums/r183/jameslleary/3930e8de.mp4

[EagleMark]

it's really ahrd to tell on a video, hit them with a timing light for a nice clear picture for yourself! That little puddling down the wall is normal, what your looking for is DRIPS straight out of the injector.

[EagleMark]

thats a trip, isnt it!? I think i only got one knock count in the entire 2nd log.
Yeah but I didn't see any 5500 RPM either, they all show some knock counts like that whether they are knocking or not, yours was normal/low counts that last log.

[jameslleary]

it's really ahrd to tell on a video, hit them with a timing light for a nice clear picture for yourself! That little puddling down the wall is normal, what your looking for is DRIPS straight out of the injector.I need a coil wire to do that, dont I?

[EagleMark]

Just number 1 (or any) plug wire like your doing timing. Not like it's going to get every shot, which it might on a coil wire? But works well!

[jameslleary]

Okie dokie...will do!
Just out of curiosity...what exhaust do you have on your Suburban?

[EagleMark]

Stock.

[jameslleary]

As in Factory? Hmmm...I would like to hear that. I baught a walker quietflow3 exhaust system for a 90 Burb, supposedly stock sound, and it is Loud! I took it off, its sitting in my garage right now, I threw a 30"case magnaflow in place, and its a little quieter.

If the Suburbans were that loud backmin 90, I dont think GM would have sold as many!

[EagleMark]

Quite, shhhh... ahhhh... I can here it run... :laugh:

Well until I blew a left rear tire last summer towing and it took out the tailpipe and damaged the muffler, since then it sounds like a Magnaflow so I left it... :laugh:

Did I mention how smooth it idles? :laugh:

When I bought it, about 10 or so years ago with 60K for $2200, it was garage kept in winter in Canada, towed a travel trailer to AZ for winter, never seen salt or winter driving til I got it. Since it was built in Canada it still has perfect paint, they did not mandate crap paint before the technoligy was there to meet EPA requirments. AC still works. Has a cargo mat in back and carpet has never seen daylight. Still very nice and get comments and wants all the time...

I've never done anything but maintence, except for the ECM hanging out under glove box as I constantly test extra ECMs, then solder in adapters for chips and sell them.

Been a good family rig, broke down once at corner store and we rope towed it home and I put starter brushs in it. Made several trips over to Seattle as an ambulance with mattress in back for wifes surgeries and luckly enough she always came home. At the time I needed something to haul grandpa and his wheelchair around, he passed and it hauled grandma and her wheelchair around, shes now in a nursing home. Hauled the kid and freinds with all their bikes to BMX races and practice couple times a week in summer, hauled the same gang to skate plaza for speed skating all winter. On it's third dog. Reminds me of my first EFI vehicle, a 1987 Red 2wd short box Chevy I bought used in 1988. I'll have to take some pictures of it, can't find any on PC? Forgot how fond I am of it... Really been a good freind to the family.

I've always had something else to offroad, hotrod, tune or convert...

[jameslleary]

Tell ya what...if you want to replace that anytime, I am going to hang on to this quietflow3, it has about 500 miles on it, and its yours when you are ready. I think it needs a resonator after it, but thats just me being picky. I have had all the loud stuff, and it got old really quick after My mid 20's...and especially now with a family.

[EagleMark]

Nah, the loud is cool around town, but that trip to Boise month or so ago let me know how loud... when I got off freeway the stereo was so loud I could hardly hear!

[jameslleary]

Even with this long magnaflow, I may install another one behind it.

[EagleMark]

I was in a LT1 car that came with factory resonator (straight through) and a muffler, then took out muffler and replaced with same resonator, so 2 resonators and sounded nice, no rap or drown. Still little loud for long trips.

[jameslleary]

Ok, update. I decided to go out and pull my throttle body off, and pull the throttle blades out....boy, am I glad I did. Had a set of spares in perfect shape, installed them and reset Minimum idle...Can already notice a little difference, and the exhaust smells really clean at warmed up idle, in gear. Have honey do's today, so If I have time, I will try to get a log. I was able to get it to idle down below 500rpm, and pretty smooth at that.
None of this necessarily means that it still wont be pig rich at Idle when I drive it...Heres to Hoping, and never giving up!

Oh, I missed out on an edelbrock 3501 mpfi manifold on ebay....sold for $127.
on a brighter note, I did score a TBI Truck 5.7 7427 PCM from a buddy that was cleaning his garage!

[jameslleary]

Mark,l
I am pulling the injectors and sending them in today. With all you have done to the Bin, my in gear idle is dead set at 108 for the BLM.
Something mechanical has to be wrong, whether its injectors, or something else.

[EagleMark]

Want to try and take some more fuel out first?

Was hoping that throttle blade issue was the issue, sure would screw things up at idle having one open and one closed.

Only other thing I would have done on your rig if I had my hands on it was oscilloscope the ignition, really shows 8 firings and any inconsistencies.

Really seems strange that log and driving is good, then idle just goes to poop... well better then poop but not right. Did you ever see drippy injectors at idle? You've done checked every mechanical possibility and I have watched your logs frame by frame, I feel defeated here... I don't like that...

[jameslleary]

Want to try and take some more fuel out first?

Was hoping that throttle blade issue was the issue, sure would screw things up at idle having one open and one closed.

Only other thing I would have done on your rig if I had my hands on it was oscilloscope the ignition, really shows 8 firings and any inconsistencies.

Really seems strange that log and driving is good, then idle just goes to poop... well better then poop but not right. Did you ever see drippy injectors at idle? You've done checked every mechanical possibility and I have watched your logs frame by frame, I feel defeated here... I don't like that...
i set my timing light reluctor on the coil cover, and I got a coil wire like result. Injectors look fine, no dripping at all...so cancell on pulling them out.
Yeah, we could take more fuel out, that would be great, but I am really starting to wonder about this camshaft.
Kinda wish I didnt give away that small cap dizzy....I still have a TPI/TBI coil on the shelf.

[jameslleary]

Hot off the press! BLMs didnt go below 111 this time.
I feel like I am in the Twilight Zone with this....Rod Serling`s voice in my head.

[EagleMark]

That didn't look bad? Try this, only warm up and drive, then pull over and disconnect power from ECM for a minute, reconnect start truck and when goes closed loop start a log.

I took out some fuel there at idle and also removed that 2 degrees from idle... I wonder if we didn't fix the issue somewhere and that 2 degrees is hurting?

[jameslleary]

I thought about that too, but advanced timing has always madenthings leaner....HMMM, off to log some more, Thanks!

[EagleMark]

Yes, but if to high can cause a misfire/preignition which really screws up BLMs.

[jameslleary]

This thing doesn`t seem happy, no matter what.

[EagleMark]

What did it do? I'm looking at log now, but without being there, it's like tuning by brail...

EDIT: Don't worry about BLM numbers it looks like you cleared memory so they will be off till it learns again. If the VE was absolutely correct they would be spot on like this. right now it is overall rich.

[jameslleary]

seems like it has richened up at the lower throttle settings, wher it was usually around 123 or so.

[EagleMark]

Exactly! You lost the ECM BLM learn, your VE fuel is actually getting a tourqe hump. This is all good, unless you didn't disconnect battery? Then bad...

Re did fuel, put the 2 degrees back at idle. Your closer then ever. Do that same thing with data log again. The only way I know to do this perfect first shot is open loop wide band, emulating. If not, it's like this last couple shots...

This is why I don't mail order tune. To much time and hard to get someone on other end capable.

[jameslleary]

Ca smog Nazi`s should be happy with this!!!
Mark, You are a Wizard!

[EagleMark]

Mark, You are a Wizard!If I were I'd have got this done sooner.

How is idle?????

How was WOT?


Ca smog Nazi`s should be happy with this!!!
Ahhh... no, we are going to have to have another bin not at 13 to 1 AFR for that... do they scantool these old rigs or just sniff?

I can't see any reason to do anything to that last bin if your happy with idle? The BLM learn will fine tune very quickly being that close.

[jameslleary]

In drive "stop light" idle is really good, Park idle after the run was a little choppy in the driveway, but the surge is gone.
WOT is good.
They Do use a scan tool,But I think just to check codes.
They usually put it on a dyno after the visual, and do 15 mph, and 25 mph tests.
It barely squeeked by last year with TPI, and an AUJP bin.
Nothing done for the dizzy, or any tuning for the cam.

[EagleMark]

I can make that pass.

Let me know when and update me how it runs next few days.

Tuning your truck reminds me of the GM Crate 290 HP engine... real PIA... :mad1:

[jameslleary]

I can make that pass.

Let me know when and update me how it runs next few days.

Tuning your truck reminds me of the GM Crate 290 HP engine... real PIA... :mad1:
Yeah...i think the LSA on that cam is 109*, and it has the old 70's 80' smog heads.

[jameslleary]

Hey Mark,
I drove the truck tonight...It felt like it was falling flat in the mid range. You think this cam wants more fuel in the mid range area?
Didnt have the laptop with me for a DL.

[EagleMark]

Yup, we started to find the torque hump in fuel VE table, I could work on the table first since I have an outline.

Were you hitting gas hard enough to find PE? PE may be a little rich now at 13 to 1...

[jameslleary]

No, was driving like an old man...just ran to the store real quick. Would fall flat after shift into second, bout 2300 rpm at that point I think.
Accellerating from a stop, if felt like i let up on the throttle after shifting. I will go out for a DL in a few here to see if I can replicate it. Will start the log from cold.

[EagleMark]

Better datalog it, sounds more like an AE issue.

[jameslleary]

Well, this is warmed up...apparently , I neglected to start the log befor I left the driveway....Doh!
The problem was actually happening at around 1300 rpm after a shift, and it feels like a brisk head wind hits the Truck...I`m sure you know what thats like, seeing as you pretty much drive the same vehicle.
Cruise power seems to have dropped a little, especially when the BLM is in the 130 range.
Fine one day, and different the next. Could this be because of the re learning process?
oh yeah, Got some 3rd gear 55 mph cruising in there as well.

[jameslleary]

HMMM....
Was over browsing Binderplanet, and read that some 5.7 TBI trucks used open loop idle as well.

[EagleMark]

The problem was actually happening at around 1300 rpm after a shift, and it feels like a brisk head wind hits the Truck...I`m sure you know what thats like, seeing as you pretty much drive the same vehicle. Nope, my runs fine... :laugh:

BLM of 130 is not the issue, your BLM are so close you could unplug O2 and run the same. It sounds like AE, but I don't think that can come into play without TPS change? Why it's doing this at this point I don't know but then again not really sure why you've had this many issues all along?

Still looking at log...

[EagleMark]

HMMM....
Was over browsing Binderplanet, and read that some 5.7 TBI trucks used open loop idle as well.Some do...

[EagleMark]

Somewhere V9 was 13 to 1, then V10 went to 14.3, so I don't know if that is what happened? Anyway here are 2, V13 is back to 13.5 to 1 and V12 has a little more injrector bias but still 14.3 to 1....

[jameslleary]

Thanks Mark!
Its already 75 here at 0746, so I had better get on it!

[jameslleary]

This is great! went ahead and used bin 13, 12 was messed up and had a rapid CEL.
in gear idle rock solid at 650, little choppy, but better. I think it may be the miles on the engine, may get better if I ever get a replacement.

[EagleMark]

Don't know what happened to 12? I enabled chcksum and saved it again, runs fine on bench. Curious what effect it would have?

14 is 13 with a little more fuel to get BLM closer, but we are down to splitting hairs.

It may be injectors or something because BLM still jump around more then expected, but if it's running good?

[jameslleary]

Thanks! I will get a couple logs the next few days....been in the triple digits the last 3 days, a/c not working in the Burb.

[jameslleary]

Ok, ECM still does not like bin 12....rapid flash
But here are 2 logs from BIN14.
1st log is from startup. BLMs went up into the 140`s a couple of times, and I think that may have been due to the fuel sloshing back from the pump, and I think I just barely made it to tha gas station.
Log 2 is after gassing up.
This bin seems to have a nice low boost turbo kick at around 3200 rpm at WOT.

[EagleMark]

This bin seems to have a nice low boost turbo kick at around 3200 rpm at WOT.That would probably be PE set to actually have PE around HP of engine... I need to figure a hack to data stream to see it.

You could find more of that? Spark is still conservitive and you've got no knock counts.

There's no way to get BLM better, didn't notice any issue with log? Without being there, is there an issue to look for?

EDIT: Here's a couple degrees spark added...

[gregs78cam]

.. I need to figure a hack to data stream to see it.

A quick look showed only this:

E7BA: BITB #$60 ; b6,b5
E7BC: BNE LE7D7 ; BR IF b6,b5
;
E7BE: LDAB L000D ;
E7C0: BITB #$20 ; b5, PWR ENRICH ENABLED
E7C2: BNE LE7C9 ; BR IF b5,
;
E7C4: JSR LFDCB ; PWR ENRICH SPARK TIMER ROUTINE
E7C7: BRA LE7D7 ;

I Would need to spend a little more time with the code to see where it goes. I am sure someone else probably already has the answers you seek.

[jameslleary]

That would probably be PE set to actually have PE around HP of engine... I need to figure a hack to data stream to see it.

You could find more of that? Spark is still conservitive and you've got no knock counts.

There's no way to get BLM better, didn't notice any issue with log? Without being there, is there an issue to look for?
Not really! Its a blast to drive now, I would say that overall it 98% better...I will blame the other 2% on maybe injectors, and the miles on the engine.
I have been compairing all of the bins to see what you did at each step... kinda getting a headache! LOL!
Can you tell at all if highway mode is kicking in?

[EagleMark]

A quick look showed only this:

E7BA: BITB #$60 ; b6,b5
E7BC: BNE LE7D7 ; BR IF b6,b5
;
E7BE: LDAB L000D ;
E7C0: BITB #$20 ; b5, PWR ENRICH ENABLED
E7C2: BNE LE7C9 ; BR IF b5,
;
E7C4: JSR LFDCB ; PWR ENRICH SPARK TIMER ROUTINE
E7C7: BRA LE7D7 ;

I Would need to spend a little more time with the code to see where it goes. I am sure someone else probably already has the answers you seek.You lurk more then you type! But when you type you have goods things to say! :thumbsup:

I think I can figure a paremeter to put it in, problem is there's really no room other then using one at a time or giving up needed data. When I used OLD Pa3 for TPS%, cause I didn't know what it did, we lost knock counts, or accurate knock counts anyway.

[jameslleary]

So, here's a question. If I want to add timing without turning the dist, should I only do it in particular cells on the SA table, or should I just increase the entire table a little at a time?

[EagleMark]

Greg, I can't find that? Were you looking at $42?

[EagleMark]

So, here's a question. If I want to add timing without turning the dist, should I only do it in particular cells on the SA table, or should I just increase the entire table a little at a time?Yes, I already added some some you can get an idea, look above for 15.

[EagleMark]

Not really! Its a blast to drive now, I would say that overall it 98% better...I will blame the other 2% on maybe injectors, and the miles on the engine.
If your 98% happy, the only way to get last 2% is an LS engine! :laugh:

Your already 30% happier then you should be with an old TBI engine...

[jameslleary]

Well, its really close to the TPI right now, with a little smoother Idle.

[gregs78cam]

You lurk more then you type! But when you type you have goods things to say! :thumbsup:

I think I can figure a paremeter to put it in, problem is there's really no room other then using one at a time or giving up needed data. When I used OLD Pa3 for TPS%, cause I didn't know what it did, we lost knock counts, or accurate knock counts anyway.

I try to read everything that goes on here, and contribute if I can.

And I agree with second part......the '7747 is just so outdated and as easy as it is to swap over to '7427, I would not even think of using a '7747 ever again.


Greg, I can't find that? Were you looking at $42?

I have a bunch of hacs in a file and they all show a lot of the same stuff, but there are a few small differences. I can't vouch for the info them, as I didn't write them.

From the ARJU.hac

[EagleMark]

I've got that zip, looked at 2 but not the ARJU where it was hiding! Thanks!

[jameslleary]

here is a log of #15. REALLY GOOD AGAIN! I noticed it got into OL at cruising....Highway mode?

[EagleMark]

Yup!

[jameslleary]

Woohoo!

[EagleMark]

Again, BLM look great. Couple knock counts at WOT high RPM which are fake! So I added a couple degrees timing.

Once you start pushing timing to a performance level you need to watch PE adder, so it is gone.

Also took out a little PE AFR... now will be a good compare for knock on your next WOT run.

[jameslleary]

Ok, I will try that tomorrow when I have some gas money...gauge is down in the Im not sure area.
Thanks!

[EagleMark]

Hard to get my 40 gallon tank off that area...

[jameslleary]

Same here. It has maybe 2 gallons in it, but I dont keep much more than that in it, because there is a guy that runs around stealing gas.

[EagleMark]

Don't try that bin! I had left the above 3200 RPM adder in, which may bbe OK, but I'd rather not...

Hopefully the other person grabbing these bins does not find out the hard way or has a differant engine needs?

[jameslleary]

Don't try that bin! I had left the above 3200 RPM adder in, which may bbe OK, but I'd rather not...

Hopefully the other person grabbing these bins does not find out the hard way or has a differant engine needs?Ok, got it!

[jameslleary]

OK, the only way I see anything getting better than this, is a new engine.
Sweet!
Log 1 is start up, and to the gas station.

[EagleMark]

:wtg:

[jameslleary]

:wtg:Just curiouse...do you think it would idle where its supposed to at 550 in drive now?
Ahhhh.....maybe we should just leave it alone.

[EagleMark]

Doubt it as that was the best improvement. I'm still not convinced your injectors are up to par?

But curious, so give it a shot!

[jameslleary]

Yup...bin 17 went back in Reeeeaaal quick.

[jameslleary]

So, a little update.
Thanks to Mark for all the help, this truck is running great...the best it has ever run for me, since I bought it from the Original owner.
I thought that it couldn't get any better, But...

On the GM Squarebody forum, one of the guys posted an upgrade project, that involved bolstering the electrical system a little. Adding grounds, and a direct line from the alternator, to the battery positive post, as opposed to charge and main positve voltage supply going from the starter and up through all the factory wiring in a system that was not designed to run EFI of any kind.
So, I replaced/added ground straps from the engine to the frame to the body.
added the direct positive line.
Started the truck, and holy Moly!
It was a cold start, which before, the engine had to crank around 7 seconds befor it started, this time, it was around 1-2 seconds, and the idle is like a newer vortec engine.
I kinda feel stupid, because while data logging, the battery voltage always showed 13+ volts at all times while running. It never crossed my mind, that my problems were being caused by a power distribution issue.
Lesson learned.

[EagleMark]

Me either?

Ground straps to body and frame? Where's the fuel pump grounded? Have you checked fuel pressure after? I'd like to know and see a new log...

[jameslleary]

No I havent...I am afraid to touch it! However, from what I can hear of the pump, it sounds like the pitch is a little higher. Fuel pressure was in spec before. It is grounded to the frame. I now have double ground straps to the firewall, from the pass side head.
And a few home made 2 Gauge ground wires from the heads to the frame.
I am most intrigued with the direct power wire though. Almost as if the Ignition system was being deprived during cranking, delivering a weak spark delaying fire up.
Will get a new log tomorrow.
Penny for your thoughts?
Hows the wife?

[EagleMark]

Penny for your thoughts?
Could be you fixed a ground issue with pump and possibly others? The start up issue is something I have been haunted with on conversions when power to ECM and EFI system like injectors is not from a direct battery source or if battery is weak, charging system is already weak at idle in non EFI cars. There's just no circuit in old cars designed to supply power needed during the high draw crank time. Weak spark, low voltage to ECM, weak voltage to fuel pump...and the ground issues. It's just a habit for me to run a heavy power wire from battery to a distribution post for all new EFI needs and grounds all back to block. Chevy trucks seem to be a good donor of distribution post and wire, but to battery not starter.

Da Wife is doing well and may be out of ICU today.

[jameslleary]

Thendoublempositive cables on Later model GM Vehicles started to makes sense after this. I was running everything on the power leads from my old carburetor ecm, that didnt have to fire injectors.
I am thinking that installing a separate power dist box is in order, close to the battery.

[EagleMark]

If you have a heavy wire you can mount the distribution closer to firewall. Just fuse it near battery.

[jameslleary]

hmmmm.

[EagleMark]

That log looks great! How's it doing?

[jameslleary]

still good, but i noticed the blms went low during cruise. Still think the engine may be a little tired.

[EagleMark]

They are so close you need to watch INT. Tomorrow will be differant.

[EagleMark]

Ha! I was looking at your log instead of the one I'm working on! Is that the 17 bin? Untouched? If not send me one.

Did you do that log after power disconnect?

[jameslleary]

Yeah, That was 17...i have not touched it at all.

[jameslleary]

Hey Mark,
I have the small cap dizzy installed, and I got the proper latency settings from a stock ASDU...runs like dooky. Is there something Im missing? Will try to get a log asap, in the hospital right now with Momma and our new baby. Tried to find the post where you posted up your bin for your burb...couldnt find it. seems to be running pretty good for the time being on a stock Ca Calibration.

[EagleMark]

Congratulations on the new kid! :thumbsup:

We lost a grandma sunday...

Latency settings would be the only difference, that does not make sense? But then nothing about your truck mad sense back then... base timing set the same?

I lost my bin in computer crash but can get it from the Suburban now it's back, been on loan to kid. I'll read it today.

[jameslleary]

Cool, Thanks!
Condolences to you and your family:(
There are some things coming to light about my burb while I have been in the hospital...lotsa time for deep thought. For example, when I installed the TPI back in 02, I had the 86 smogger heads that came on the GMgoodwrench engine. I also ran stand alone fuel lines, the return was a 3/8" that i ran to a 3/8 nipple that I had installed in the filler tube.
With the required dual cats, and AUJP, that baby passed smog like a champ...cleaner than most newer vehicles.
Fast forward to 2009.
Changed to TBI heads, the comp TBI/TPI cam....ran real good, more low end.
i swapped the fuel lines to using the 86 main and return lines on the frame. Return line on the truck is 1/4....pretty small compaired to what I had.
The idle got niticeably rougher, and the next smog barely passed, and after that, the cats just quit working....which made me swap to TBI.
Return line will be changed before the next 350 mile trip for thanksgiving.
Since installing the small cap dist, and using a stock bin, it has been running really good,,albeit a little on the rich side, according to my nose.
PROGRESS!

[EagleMark]

Fuel pressure would show an issue with return line. Still strange that chip should work with or without latency settings changed, correct latency would make spark more accurate.