TBI ignition control module

[typhoonss]

Have a question for all you TBI lovers out there. I have had this truck for just over 6 years. once a year the Ignition control module goes bad, this is the 2nd time it has completely gone out where the truck could not start but usually just kills the timing advance so I can at least limp home if needed. I have replaced all the power and ground cables in the truck with marine grade and marine heat shrink but this issue keeps happening. I have replaced the entire distributer with a GM delco one about 3 years ago. I have tried performance ones, gm replacements advanced auto ones, and have gone to the junkyard and got the one that came in the truck, no difference. Just trying to see if anyone has seen this issue as I have spoke to ultiple master techs and they have no idea.

Thanks All

[stew86MCSS396]

They don't like heat. In the past I thought the little grease packet that it came with it was dielectric grease but turns out it's a thermal paste. Some have gone to extreme measures and purchased the good stuff used with heatsinks on CPUs. I seem to recall someone on this site relocating icm away from the heat, too.

[delcowizzid]

Bolt it on a 8mm thick piece of alloy on the firewall with some heat transfer paste to work as a nice sized heatsink I've had a few that start idling bad sitting in traffic heatsoaking normally sorts them out changing location

[C2500]

Have you replaced the coil,plug wires??

[dave w]

The attached screen shots show a normal SA and very odd SA. I wonder if over time, your SA starts looking odd?

dave w

[dktool]

The attached screen shots show a normal SA and very odd SA. I wonder if over time, your SA starts looking odd?

dave w

That odd one looks like a limp mode, I thought the module only controls advance in limp mode, and under normal conditions it only signals cylinder static advance and the emc/pcm timing table does the rest. ??

[tamperedchevy]

it seems most don't last long but every once in a while, one finds a good ICM that lasts a lifetime. dang even the acdelco ICM failed?
are you running a modded computer?
i just had one fail a few days ago(it was two weeks old) the one i replaced was fine. i shoulda left it alone. back to the point. i had just patched my 7747 with the spark advance hack and it failed that evening...coincidence?

[typhoonss]

sorry been out all weekend. The ICM's have been in the stock computer when it was a 5.0 and failed, in a very light modded 350 with a new distributer and failed and now in my modded 357 and failed. The timing/SA does not look wierd. This time it died and the truck was not even warmed up, I was ideling for about 15 minutes but it was 50 degrees out, shut the truck off and 2 minutes later tried to start and no fuel as the ICM does control allowing fuel. I have had 3 different tbi trucks and this is the only one that has ever given me issues, all were modded and all had headers full exhaust, electric fans, ignition systems or msd coils and moroso 8.65 ultra 40 wires. The coil and wires are about 1yr old as I replaced them right after the ICM died a year ago, for some reason it is about every year which makes no sense. I am gonna try the Artic Silver 5 thermal paste I use on my overclocked gaming computers and see if that helps. I was just throwing this out there to see if anyone else has had this same issue where it dies once a year, I usually put about 10,000 a year on the truck. Anyway thanks for the responses.

[stew86MCSS396]

Bolt it on a 8mm thick piece of alloy on the firewall with some heat transfer paste to work as a nice sized heatsink I've had a few that start idling bad sitting in traffic heatsoaking normally sorts them out changing location

Seem to recall if you do this, can't remember which wires but they need to be twisted...

[tamperedchevy]

i had two icms go out in 3 weeks now. but my connectors where a little loose.(maybe they loose connection enough with engine vibrations to shorten the icm life?) maybe check your pigtails? also my GM icm never fails. but every aftermarket one failed so far. really leaning towards--maybe they are all junk? just some ideas..

[typhoonss]

One thing I think I have noticed over all 6 of these icm's failing is that it dosen't crank as fast when I start the truck for about a month before it dies. I just think it is very weird it is every year, not a few months or at random times but almost exactly a year apart these things die and dosent matter if gm or aftermarket or performance ones they all fail same time about 1yr. So I am keeping a space in the truck, I have the tools to change it out quickly so if it happens I can change it. I will also see if next time it starts cranking slower when starting and see if that is a side effect before it dies. But we will have to wait for a year because that is the pattern so far.

[typhoonss]

I have never seen a SA like that in any datalogs and I was datalogging the day before the icm went out. The only thing I notice is it gets harder for the motor to crank over or should say it's like the battery being low and cranking slowly but the battery is fine. Once I replaced the icm it cranked over normally. The icm is very weird piece, I have had it just take out the timing advance and the truck would still run 2x, I have also had it just die where there is no fuel or spark 3x and I have also had it take out the entire distributor.

[grumbolt]

The attached screen shots show a normal SA and very odd SA. I wonder if over time, your SA starts looking odd?

dave w

would you say my icm is bad Dave? when my engine gets up to operating temp, it acts like the timing is way advanced and is hard to start.

attached is a screenshot of the wbo2 spreadsheet with the log pasted into it...

16602

important to note, the battery voltage was around 13.5 most of the log, but at the end it was down to around 12.5v i originally suspected the erratic readings due to the voltage going south... the engine was also around 219 degrees at its peak....

[dave w]

I don't know if the ICM is faulty or not. Usually an engine won't start with a faulty ICM.

The odd SA might be due to the data stream definition or .adx file.

I would reprogram the chip with the Altitude Spark Bias set to ZERO degrees, leave the other parameters unchanged.

dave w

[Fast355]

I don't know if the ICM is faulty or not. Usually an engine won't start with a faulty ICM.

The odd SA might be due to the data stream definition or .adx file.

I would reprogram the chip with the Altitude Spark Bias set to ZERO degrees, leave the other parameters unchanged.

dave w

Leave the altitude bias alone. Not sure why people just program this out with no knowledge of what it is actually there for or what they are doing by removing it. The weird datalog SA is because the logging aoftware is not recognizing a negative number. Zero'ing the bias is adding that much timing to the whole timing map. If it was a bias of 9.81 and you set it to zero, you have added nearly 10° across the entire spark map.

[grumbolt]

Leave the altitude bias alone. Not sure why people just program this out with no knowledge of what it is actually there for or what they are doing by removing it. The weird datalog SA is because the logging aoftware is not recognizing a negative number. Zero'ing the bias is adding that much timing to the whole timing map. If it was a bias of 9.81 and you set it to zero, you have added nearly 10° across the entire spark map.

I had not messed with the altitude spark bias in the past, but it was set at 0.

the specs for the engine in its stock form calls for 0 timing and it is set at that...

i have changed out the module and had the alternator tested..
it seems that when i installed the engine in the buggy, i ran the "L" terminal from the alternator to a light bulb then to ignition power... this is how it is represented in the schematics.. in poking around i have seen where a resistor is wired in series with or instead of the lamp on the cs130d alternators and suspect that the bulb in the tracker dash doesnt pull the same amperage as the bulb in the sonoma dash.. i will be ensuring the charging system is operating properly before the next logging session..

do you know how to make the ecu retard the timing when trying to start the engine when it is hot?

thanks, in advance!

[Fast355]

I had not messed with the altitude spark bias in the past, but it was set at 0.

the specs for the engine in its stock form calls for 0 timing and it is set at that...

i have changed out the module and had the alternator tested..
it seems that when i installed the engine in the buggy, i ran the "L" terminal from the alternator to a light bulb then to ignition power... this is how it is represented in the schematics.. in poking around i have seen where a resistor is wired in series with or instead of the lamp on the cs130d alternators and suspect that the bulb in the tracker dash doesnt pull the same amperage as the bulb in the sonoma dash.. i will be ensuring the charging system is operating properly before the next logging session..

do you know how to make the ecu retard the timing when trying to start the engine when it is hot?

thanks, in advance!

From what I remember the ECM does not control the timing during cranking. EST bypass circuit is enabled it cranks off the distributor base timing until about 250 rpm is reached.

[TeamSlewis3]

But even with the "base" timing map in the icm code it would still be WAY dependent on how many HC's he's actually got floating around in the cylinder. Maybe it's flooding and no amount of spark correction will help. OR the opposite could do the same. we were always trained the switchover controlling was @ 450 rpm. If youv'e ever had to revive a no starting RX* you guys will know what I'm saying about wasting time with timing, how wet is it inside when the event happens?

[Fast355]

But even with the "base" timing map in the icm code it would still be WAY dependent on how many HC's he's actually got floating around in the cylinder. Maybe it's flooding and no amount of spark correction will help. OR the opposite could do the same. we were always trained the switchover controlling was @ 450 rpm. If youv'e ever had to revive a no starting RX* you guys will know what I'm saying about wasting time with timing, how wet is it inside when the event happens?

If its freewheeling on the starter that is one thing, but kickback on the starter is over advanced base timing or a weak starter.

That being said the stock 100K mile Vortec 350 PM mini starter from my 97 Express van has no issues spinning over my 11:1 383 with a Q-Jet sitting on it with 14° initial timing. It cranks at 220 psi. It may be time for him to upgrade the starter, test the battery or replace the cables.

[dave w]

Leave the altitude bias alone. Not sure why people just program this out with no knowledge of what it is actually there for or what they are doing by removing it. The weird datalog SA is because the logging aoftware is not recognizing a negative number. Zero'ing the bias is adding that much timing to the whole timing map. If it was a bias of 9.81 and you set it to zero, you have added nearly 10° across the entire spark map.

How can you accurately say "with no knowledge"?

I can accurately state, you don't know everything!

dave w

[Fast355]

How can you accurately say "with no knowledge"?

I can accurately state, you don't know everything!

dave w

I never claimed to know everything, but I do have a fair working knowledge of what the bias values do in the code and also what happens when someone just zeros them out. I have been through the actual code in the motorola assembler and dissasembler as well as worked in the $0D Hac enough to make my own XDF and write my own lines of code in $OD. I also have a fair knowledge of the workings of the MAF OD and MAF OD MPFI code. The datalog is doing those weird numbers because the timing advance is negative in those areas. As soon as the timing value is positive the weird mess goes away. That is why whacking the altitude bias appears to fix it. It is doing the same thing as offsetting the whole timing map the same number of degrees advanced. The bias is simply there so that the table can have a negative number. Guys used to ignore the bias value and several $42 ecu and xdf files were written without the bias value being subtracted out.

Long story short, leave the bias alone, make the timing map positive, make sure the coolant xompensation is not retarding a ton of timing at the coolant temp the engine is running and that there is no knock retard and those weird values will go away. If the engine actually needs negative timing there, simply know that those weird numbers are negative timing values.

[1project2many]

The ecm generally is not involved in controlling timing below 450 rpm. In order to retard spark timing during crank one would set the timing with a base angle of less than zero degrees. The reference angle in the chip should be adjusted to match the actual angle of the distributor so the timing tables continue to be correct. Early TBI engines were set at 6 degrees then GM moved to to zero degrees. I'd love to have the "real" answer for that change.

Fuel delivery is delayed during cranking as well, generally by a number of reference pulses. "Back in the day" a properly adjusted and not leaking Quadrajet would usually allow the engine to start with the shortest application of the key if the engine was warm. By working with IAC Park position or initial IAC position (depends on cal) and the number of reference pulses before fuel is enabled it's possible to get an EFI engine to start as quickly.

Speaking of quick starts, I've switched a number of GM vehicles over to use Ford in-tank pumps. I have replaced more GM pumps than any other make. And I've worked on Ford vehicles with over 300,000 miles on the original pump. Side benefits seem to be a better check valve and less time before the system is at full pressure. I believe a 99 or 2000 Lincoln Navigator w/ V8 is the application to look at.

The most common failure modes I used to see with these ICM's are no spark when hot, no spark ever, and no reference pulses to ECM. Often a "No spark hot" complaint could be traced back to a faulty pickup coil. Sometimes I'd even get a truck that had received two or three modules replaced "elsewhere." It's much easier to get the problem fixed in one try when someone else has already tried all the easy solutions.

I keep hearing that ignition modules are garbage these days. Folks say you can put in two or three in a row just to get one that works. That alone could make diagnosis a nightmare. But the basics still apply! Ensure you have a good 12V supply to the coil, especially during cranking, and to the module. Ensure the module is properly grounded. Clean the mounting surface and use heat transfer paste (not dielectric grease) between the module and distributor. There are two vent holes in the bottom of the distributor. They are protected by tiny screens that get plugged. Clean them! I've actually installed ported vacuum fittings on the bottom of distributors to help keep air moving through and to reduce the buildup of nitric acid in the dictributor. I promise it helps the components last longer.

If the engine is cranking slower before the module dies, I have to ask if there's any chance you're having battery or charging issues? Is it always at the end of winter? When more power is directed to the starter there is less available for the coil. The ICM controls current through the coil so the lower the voltage, the longer the ICM leaves the coil turned on. Although this shouldn't change the total amount of heat generated, I have to wonder if shorter bursts of higher current may do less long term damage than longer on times with less time between for cooling. But ultimately we're talking about microseconds and the difference may be academic.

I agree that the "wierd" timing values posted by grumbolt appear to be normal values misrepresented by the datalog software. It's possible to edit the definition file so the timing displays correctly.

[TeamSlewis3]

You know I was talking to an old trans builder "mentor" whom I watched for a couple weeks with a service writers FORD F-150 ......... GOTTA SWITCH TPOUGHBOOKS APPARENTLY

[TeamSlewis3]

Ok so the freind is a fairly savvy fellow but kinda always gives me greif because I "work too hard" . Ya know when I met em in our 30's he already had race cars and drove one of the vette's to work. Long story short I sat back patiently as I watched our service writers 50 somethin 289 truck just eat him up on what he SWORE was "fuel loading" . He ahad done a tune up already, then modules coils, scopes..... I said looks like a burn line issue. Couple days later he found that cracked plug. My question is this: those screens they put in the bottom of the lower plate I've seen clogged ,green , no srceen, But I believe it is a heat issue that over time a small voltage problem whether groung or power finally deathnails it. High humidity? Not enough time ,short trip condesation?But I'll agree with the previous poster I have NEVER in 30+ years seen an ICM come back from the dead or cause an obvious data issue thats an anomoly that can't be felt in the foot. I have seen ECM's do weird stuff and give false data that if correct can only be captured by scoping nputs, even then, output can be incorect w/out any codes. Seems like these old ones can have tons wrong and no codes..... the early days!! Carb guys going SEE thems junk! I'm kidding. I loved my elecrtronic Q-jet opening up those flaps in that hood, and it SOUNDED way cooler than the Cross-Fire pace car I had that did the same. So I mentioned my knocking or phantom knocking and he just asked "why not just go with the $50 HEI?" and I know it goes against most thinking but I'd like to run the HEI with external VORTECH the ICM driving the timing. Any Ideas?

[1project2many]

My first two EFI systems cost me $200 but had to jump in the dumpster to remove a bunch of parts. One was an '83 Crossfire (the manifold is on my pickup) and the other was TPI. I spent years asking people how to make changes to 'em. Kept getting asked why waste my time? Cause in 10 - 20 years you won't find a carburetor in the junkyard.

Most of my ignition modules last for years. I actually changed one in my '57 two summers ago. It was a used OEM module I put in when I switched the truck to EFI in '93. For a while my '99 Vortec truck was giving me fits with intermittent misfires that appeared to be a few different issues. I found coil burn through twice, a bad module once, and a bad rotor several times. It turns out the power wire to the coil and module was chafed and shorting. I'm guessing the power interruptions were causing misfires that led to the other issues. After the wire was repaired the truck runs very well.

I'm gonna say "possibly" to the external Vortec module on HEI. There's no bypass mode built into the Vortec or LT1 module. And there's nothing to convert the crank signal to a square wave. So I'm thinking that if I only had access to automotive parts I'd investigate using the HEI module to trigger the LT1 / Vortec module. If you can do that you'd move the high current switching out of the HEI module. Research the signal from the ecm / pcm. If it's driven low similar to a coil - signal then you may be able to wire the coil- from the HEI module directly to the pcm input on the Vortec module.

[tayto]

i am curious about the ford pump being used in place of the gm pump. the "standard" seems to be upgrading to a tpi or vortec pump. this one is new to me. also, a tip I picked up from fast355 many years ago is to braze/plug the fuel pressure bleed off port inside the injector housing. your injectors & o-rings have to be up to the task, but it makes a noticeable difference when starting a TBI vehicle.

[1project2many]

i am curious about the ford pump being used in place of the gm pump.

I've changed far too many GM pumps over the years. This seems to have gotten better but back in the days of TBI and TPI and through the L31 they'd often fail with 100k to 120k. I found some correlations such as routinely driving the vehicle with less than 1/2 tank leads to more frequent replacement, and that you could sometimes identify the "cheap" pumps by physical features regardless of the brand on the box, and that Bosch branded pumps almost always lasted longer. But at the same time, there are Ford and Dodge vehicles that go for 300,000 miles without needing fuel pump replacement. GM, and most companies I'm aware of, use brushed DC motors for fuel pumps. Brushed motors transfer current to the armature through carbon brushes that are in contact with the commutator, a dedicated part of the rotating armature. In most motors as in the GM pump the commutator is made of copper and the brushes are held against the commutator by spring pressure. GM pump failures are almost always because the copper commutator wears out. Post-failure inspection reveals deep grooves in the commutator and at least one or two places where there is insufficient copper to allow a strong enough field in the armature to start the pump. It is very common on these vehicles to see dark rust-colored fuel draining out of the dirty side of the fuel filter. This isn't actually rust though. It's copper and carbon from the pump. Strangely enough, when we replace a Ford filter with high mileage we don't see the same buildup.

With all of that in mind, it just seems like a simple question to ask why a pump from another make won't work. The short answer is that it works fine. IIRC the pump is 3/8" output while the fuel sender input is 5/16." The pump body is shorter and you might need to find a different sock for your tank. You'll also need a different connector for the pump but the one I get comes with a new connector. This image is of a similar pump with the connector and sock.

[tayto]

i am quite familiar with DC motors & brushes being an elevator mechanic. i should have asked more questions about the ford pump, mainly the pickup and what you've done/used. the bottom of the pump obviously won't fit the stock sock. FWIW, that pump looks very similar to the one I just changed in a friends '98 cherokee. I am doing a pump replacement in a TBI truck soon, so i will maybe spend some time exparinenting.

[grumbolt]

im just getting back to this thread, work has been very hectic..

thanks for all the replys and ideas...

so far i have found the alternator was only putting out 12.5 volts.. i have installed another connector so i can connect the "s" terminal to the battery positive.. i now have 14.2 to 14.4 volts at the battery depending on loading (all the lights and fans on vs off)

during the slow start hot situations, the voltage would drop do 11.5 volts or so... maybe it was simply a charging issue..

i have changed the module as well..

when i get a chance to take it out again ill get another log and report back what i find and if the issue is resolved.

[1project2many]

i am quite familiar with DC motors & brushes being an elevator mechanic.
I will keep that in mind for the future. I had received a couple of PM's asking about the failures so I thought I'd describe the issues.


i should have asked more questions about the ford pump, mainly the pickup and what you've done/used.

Ahh... I have a great relationship with several auto parts stores. I generally go through their selection of fuel socks until I see one that looks good. Ford fuel socks have a small ring that is designed to fit over an aligning pin on the pump. The last conversion I remember doing required a sock that was oriented 90 degrees to the one that came with the pump.


FWIW, that pump looks very similar to the one I just changed in a friends '98 cherokee.
I've been doing these swaps for abut 10 years. I seem to remember looking at many pumps when I first tried switching. Chrysler pumps are similar also but they use a "pump module" which doesn't have a separate pump. I *believe* that the Ford pump may have been cheapest. Or it was the only one available that day and I've just continued using that same part.


i have changed the module as well..
We now return you to your regularly scheduled topic...

[tayto]

I've been doing these swaps for abut 10 years. I seem to remember looking at many pumps when I first tried switching. Chrysler pumps are similar also but they use a "pump module" which doesn't have a separate pump. I *believe* that the Ford pump may have been cheapest. Or it was the only one available that day and I've just continued using that same part.


We now return you to your regularly scheduled topic...
I believe in '95 the Cherokee went to a pump module, but the pump is replaceable by itself, as that's what we replaced. the bosch pump originally came with a sock which is inserted over a post with a circlip holding it on, sounds like your ford pump. I will try to get pictures.

[grumbolt]

I agree that the "wierd" timing values posted by grumbolt appear to be normal values misrepresented by the datalog software. It's possible to edit the definition file so the timing displays correctly.


excuse the noobness, but what would have to be changed? and would it be in the A217 $0D TP5 v250.adx file?

would it be as simple as changing the "range low" in the picture to a negative number?
16631

[tayto]

Acdelco TPI pump (Left) & Bosch Cherokee pump (Right)

[1project2many]

excuse the noobness, but what would have to be changed? and would it be in the A217 $0D TP5 v250.adx file?

would it be as simple as changing the "range low" in the picture to a negative number?
16631

Hi,

I apologize for missing this question.

In the right side of the picture, below the box with the formula, you must check "signed" to indicate to the computer it should interpret the data as positive or negative numbers. As you guessed, the "Range Low" must be lowered. I believe -25 should be good. I will attempt to look through notes or other files to double check that the formula is correct.


Acdelco TPI pump (Left) & Bosch Cherokee pump (Right)

http://www.gearhead-efi.com/Fuel-Injection/attachment.php?attachmentid=16640&stc=1&thumb=1&d=1617204723


That looks like the two style pumps. Most of the Bosch pumps look similar. Some of the early TPI Y cars used Bosch pumps. Like the Ford cousins, they seemed to last much longer than the OE Delco models. Maybe the replacement models fit with no additional modifications.
https://i.ebayimg.com/images/g/pkgAAOSw2XFUgKcJ/s-l1600.jpg

I'm thinking I used the Ford version because it's stocked at the local store and because it has worked for me repeatedly.

[tayto]

Bosch p/n 69225 is equivalent of the EP381 (vortec trucks) and will interchange with TBI & TPI pumps. I will use this in the future, thank you for your information.

[grumbolt]

Hi,

I apologize for missing this question.

In the right side of the picture, below the box with the formula, you must check "signed" to indicate to the computer it should interpret the data as positive or negative numbers. As you guessed, the "Range Low" must be lowered. I believe -25 should be good. I will attempt to look through notes or other files to double check that the formula is correct.





awesome! thanks

should i also change the "alarm low" value as well? and if so, what value would you suggest?

[1project2many]

should i also change the "alarm low" value as well? and if so, what value would you suggest?

The alarm values cause the software to provide a warning. If you'd like to prevent the warnings you can adjust the alarm low.

[grumbolt]

The alarm values cause the software to provide a warning. If you'd like to prevent the warnings you can adjust the alarm low.

thanks!

[TeamSlewis3]

So this is gonna sound crazy, but to your carburetor statement, I just happened to go to the junkyard this past week and lo-n-behold there it was...... An Old Electronic Q-Jet and HEI setup on a still in the Camaro 350 with ECM and all !!??!! I'll be back to maybe grab the whole Engine altogether with harness, comp, probably for couple hundred since apparently from the looks of it , it's been there for @ least 10-15 yrs,and no one is interested! As to my own issue of a 4.3 to 350 transplant with some kinda crazy logic of a Turbo 400 Trans behind the V-6 and the impossible task of finding a .bin that doesn't exist.... well it actually does. I "THINK" it's been right in front of everyones nose but several members had tried figuring out to no avail. I've got a post about this transplant eating my lunch on the timing and trans side all the way from the ECM to the ESC module. Tell me what you guys think. To me it appears the reason there will be no kickdown switch on a 89' model with a Turbo 400 because it in fact DOES NOT NEED IT to physically be there anymore. And I spent quite a bit of time hunting it on this factory 89'c1500 and it is NOWHERE to be found. I can't match the right mask and bin but i will now that I'm certain it can only operate one way using ANY 3spd .bin by using the VSS, MAP and TPS deltas and data from brake switches to operate the kickdown solenoid in trans that used to need the switch before 1227747 ECM and pin A7's control over it. It's not TCC to chase after because after all... it doesn't have one. However ALL the timing corrections, AE, PE, and every problem my truck is experiencing I believe is bieng cause by just the Turbo 400"s tunes operation not being understood and set properly for not the listed TCC stuff thats everywhere in the.XDF,confusing as hell and garbled up to look all important, but the items that need set for TRANS KICKDOWN to be handled, even though it's not actually listed in there in a way only GM engineers could undestand !!!!!!!!! Sorry for the rant but I been BEAT DOWN by this SIMPLE swap. 12 yrs I worked for them guys n NEVER saw a need for a Turbo 400 behind a V-6....or ever even saw such an animal till now. Like real Unicorns!!

[TeamSlewis3]

Also speaking of pumps, When the vehicle was backfiring and sputtering during trying to find out if this or that .bin was gonna work I knew it sure felt lean and no power. I didn't know wether it in fact was and it seemed impossible that it could be, since I had just replaced the pump and stariner in the early diagnostics with a factory DELCO 386 or 381 whatever it was and strainer. I usually keep both the 96' and up Truck pump and the one for TBI just for general purposes. Now I just kinda stumbled upon it needing a pump on top of everything else, by running the pressure test FIRST, since thats what it felt like at first. Whats the strangest thing is it was running fine for the customer prior to the engine swap, and he mentioned nothing about either shifting issues or power problems. Just the fact the enginge needed to come out and EVERY gasket on it replaced due to oil pouring out, and the timing chain being able to almost touch together when sqeezed in the middle....so I actually talked him into the swap since I basically would need to build an engine it might as well be the 350 sitting in the corner of the shop. That's how it started. When I took the fuel filter off to due the test it was immediately clear someone had put a top quality chinese filter on it that when shaken made a quaint rattle paint can sound, which might have explained the fact it had been running on 2 psi of pressure,...yes 2 psi of pressure, for I have no idea how long. But over my carreer I've seen some TBI's run at that astonishingly low pressure, and the customer is definitely a speed limit obeyer on his way to church every Sunday, which might be why he didn't mention any issues other than the oil pourin out! So I thought "well since it's gotta have the injectors swapped from V-6 to V-8, and this tune's being cantankerous, I'll play it safe and use the adjustable regulator setup I had used with success on my 383 build with the hogged out TBI and 454 injectors"..... dammit at 12.8 volts, and the regulator cranked all the way down, that DELCO can only manage a measly 11 psi a fuel pressure, and that was DEADHEADED!!!!! So since I've been independant mostly working all makes and models for about 15 yrs I'll have to throw my hat in the DENSO ring. It just seems not a single manufacturer can make decent reliable ANYTHING these days. Carter, Delco, Airtex, Bosch all have taken a nosedive on quality and reliability. And to me it's not just degrading quality of pumps and such, but rather everything seems cheaper and more expensive. Getting harder to go with brand X you use to count on. I purchased a timing set by "Cloyes", the american company that's been around for longer than I have been alive, and I probably first used in 1985 Autoshop in high school. It was for the depressingly engineered 3.6 Cadillac SRX I think, and even though MOST of the parts in the really complex kit looked good to me, there was that one double sprocket idler that I could tell didn't match the othe component's in the kit. It went about 5 min before I shut it down just in time to NOT have to buy that cust a new engine. It had seized and snapped off the bolt.but the case wouldn't let it get far enough out to bend any valves. I called the company to express my shock at what happened only to find they know about the poor quality parts causing issues ....... but yet they are still selling the kit........knowing. SERIOUSLY guy admitted they knew which was just even more depressing. They warrantied the part but I chose to go back with the I believe 6th design factory GM components at three times my quoted price. The sun is out today, I was smart enough to grab that diode or rectifier(?) right by my trucks ECM that when I think the TCC on the truck tried to engage or whatever had blown, I got a new ESC module, and hopefully my G1 adapter and 24 pin prom socket conversion and a new calibration will cure my Blues.... that and some good music....Black Label Society or VolBeat or Shamans Harvest..... yeah gonna be a good day!