Hi everyone. So we did the engine rebuild..sorted out some heater pipe issues to the throttle body, actually bypassed that feature as my pipes were bad and I couldn't find a source to get new ones. Not sure if it has any tie in with my current symptom.
Car starts right up, idles ok, but once I step on the gas pedal, it starts to sputter and has no power. Bucks even.
No codes were triggered initially...So we did as the FSM suggested, unplugged the TPS to see if the ECM/ADLD (sp) ? systems were working, it threw a 22 code , which is for the TPS, but also a code 26, for some part of the ECM unit that has 4 parts? So we just replaced the ECM, TPS, coil pack and ICM..most of which I had a LTW on thru autozone so didn't cost me anything. Still no change.
Oh yes, we had previously replaced the fuel pump, fuel filter and sending unit, as we were having a fuel gauge issue, Also new from the engine rebuild 300 miles ago are the plugs, wires, cam sensor, cranksensor, and fuel injectors. Any ideas?

You didn't install Bosch plugs did you?
These seldom work well in the Bonneville engines.

First up, Id double-check the order of the ignition wires.
It happens all the time that a wire gets swapped with another--even pros make this mistake once in a while.
https://www.justanswer.com/pontiac/31er ... ntiac.html

Am I correct in assuming that you've checked the TPS for a very smooth voltage change as the throttle is opened?
Testing details
http://easyautodiagnostics.com/gm/3.8L/ ... n-sensor-1
The TPS is an adjustable sensor on the 89, so if it has been removed, it needs to be adjusted, as follows:
http://easyautodiagnostics.com/gm/3.8L/ ... n-sensor-4

You can unplug the MAF sensor and see if that improves the acceleration issue.
You can also test the MAF
http://easyautodiagnostics.com/gm/3.8L/ ... f-sensor-1

You can try cleaning the MAF sensor with MAF sensor spray cleaner.
Other cleaners leave dirt collecting residues which will cause a recurrence in a short while.
The computer uses the MAF sensor to determine how much load the engine is under.

Hi thanks for your reply. Some other factual tidbits.. The sputtering would occur just about at 2000rpm.. It now throws a code 22.. The TPS.. Which we just replaced today.. And it didn't change the sputtering.. My mechanic friend will return tomorrow and adjust and /or check the wiring... The spark plug wires, if out of sync, wouldn't that give me a poor idle also? She starts and is idling pretty good...

A code 22 will appear if the engine is run while the TPS is disconnected.
If the code was cleared after you ran it that way, then the TPS adjustment or wiring are to blame.
Yes, wires should affect idle, if mixed up but it only takes 30 seconds to double check.
In addition to what I've listed earlier (TPS, MAF, bad plug), other suspects include clogged exhaust (easily checked with simple vacuum gauge).

With the engine warmed up at idle, there should be a steady reading of about 21 inches of vacuum.
Hold the engine RPM at 2000 and watch the gauge. The pressure should momentarily drop but then go back to being very close to what it was at idle.
If the pressure slowly drops, then you have a restriction in the exhaust system.
This would either be damage to the exhaust system or a clogged catalytic converter.

sounds like a plugged cat - unbolt the cat to downpipe ( letting exhaust out)and bypass the cat - if it runs better, its the cat - replace or punch it out:break up the 'biscuits' so you get air flow:
dont drive, you will overheat and kill the engine.

_________________
poverty forces one to do unorthodox things

2000 SSEi
past rides:
1996 SSEi
1992 GTP
1987 Grand Am

Hi.. The catalytic converter is maybe 15 months old. Maybe 1200 miles on it..? Had to replace it to pass my smog test here in ultra strict California last year.

yeah I use the same one here - test it anyway - how is flow at tailpipe?

_________________
poverty forces one to do unorthodox things

2000 SSEi
past rides:
1996 SSEi
1992 GTP
1987 Grand Am

The new mechanic working on it seems to think it is electrical in nature.. He's had the car going on 4 days and so far nothing has been found definitively...

No new codes. It starts right up, idles ok, if cold stumbles and misses once step hard on throttle. If early can be ok. Once warms up still can only give it an easy poke with the right foot.. Otherwise misfires again... Gas is clean.. New rebuilt Bosch fuel injectors.. New fuel filter.. New sending unit and fuel pump..

Still dealing with this problem. Brought it back to an electrical auto specialist, at least that's what his shop sign says. Lol..he seems lost too..had the car a week. Talking about starting with replacing the battery and alternator? I explained that the battery has like 200 miles on it. The alternator was rebuilt upping the stock 105 amps to 140 or thereabouts by a specialty shop about 2 years ago. I would think he could test that kind of thing and, really, will it have any bearing on the car running poorly when cold, but once warms up it's better.? Plus it starts right up and idles ok.
I had to remind him what all I have replaced since rebuilding the engine a few months ago and after this problem surfaced. : ICM, coil packs, TBS, fuel filter, sender and pump! HELP...lets wake up our 1989 SSE genius gentlemen on this fine forum and figure this one out..I've come too far to give up yet! Thanks..

Spritz water around the plug wires at idle in a dark place and look for arching. I once had a plug wire with very thin insulation shorting out.

_________________

WHITE WHINE - 1992 SSE Supercharged 236.26 ci (.040 Over) 15.090 at 90.2 MPH on old engine w/ slipping trans & melted O2 sensor - Gen 3 M62 and matching TB, Gen 2 Pully, Zillamotorsports Ported LIM, YT 1.72 Roller Rockers, SII FPR & Injectors, Hypertech Thermomaster chip w/ 160 Thermo, TransGo Shift Kit, Infinity/Pioneer Speakers & a 10" Alpine Type R Sub, all the watts, 140 amp Alternator, Ricepipe CAI w/ heatshield, Pilot Angel Eye Foglights, Clear Corners, '02 17" Chrome Bent 5's, Magnaflow F-Body Muffler and Hi-flo Cat, Ceramic Coated Ported Exhaust Manifolds, Fan Override, Monroe Reflex struts, red calipers
2009 G8 GT - Sport Red Metallic, loaded, SOLO Axlebacks, Rotofab Intake, Tuned, autodim mirror, removed intake manifold cover, HSV GTS triple gauge pod, two tone red-hot shifter and HSV SuperSport steering wheel, GXP rear sway bar and diffuser, 3.45 diff and various Camaro suspension bits, LED Taillights

Has the Mass Air Flow Been checked? The fueling system on the older Bonnevilles is dependent on that MAF reading correctly.

Hi.. Yes just spoke with current mechanic checking on it. Said the maf sensor and throttle body sensors were reading properly. My question, is what sensors component should, etc could be messing up with the car being cold? Once it warms up runs better without as much hesitation... We had replaced the temperature coolant sensor before it began acting up.. Again most parts are new.. Had rebuilt an engine from a 1990 Buick reatta.. Same vintage.. Vin c, etc.. Electrical stuff replaced were battery, ignition coil and ignition module, new wires and plugs, both ac Delco professional line... New fuel injectors, fuel pump, sending unit, fuel filter... The list goes on..

So, my mechanic put the car on some kind of fancy scope, showed me like an occilloscope wave readout, that seems to show the 3 and 6 cylinders are having a drop in voltage or something. Based on some other readout data, he is leaning towards an internal engine problem causing low compression, such as a ring that didn't seat right or something? What? Huh, you talking to me? Why isn't it all the time then, and why once warmed up does the sputtering and misfires stop? He says once warm the rings expand and temporarily correct the issue. He wants to do a compression test to rule this possibility out. Lets see ..

On my 2000+, a misfire at startup was a failing ICM.
3 and 6 share a coil, so it could be the coil or the ICM--despite being new-ish.
No quality control on many parts nowadays.

If it doesn't have it already, you may want to look in to converting over to the delco ignition system. The Magnavox system that came stock was known to be problematic from the start, and when it failed, often required the entire unit to be replaced.

Instructions and parts lists can easily be sourced with an internet search.

_________________
~Randall~


1993 Buick Park Avenue - 197k - Some odds and ends done - Simply won't die
1994 Buick Regal - 78k - Bone stock - Always ready for a good kicking
1990 Oldsmobile 88 - Gone to a better place

The latest is.. The crankshaft sensor! It was loose.. Maybe not tightened properly when I changed it during the recent engine rebuild. The pigtail connector also seemed beat up and had some silicone type hook smeared around the end wires.. We changed that and the cs sensor.. And he said it fixed the problem. We shall see!

Ran ok for a few hours, then started a different type of miss. Fully warmed up, two flat cylinders. Had it towed to the mechanic, he tested a few things, then switched around the coil and ignition module connections, it ran better. I just had him change the coil a few days ago.. Told me how to check it out if it starts missing again, but I think I will just get a new module and put it in. Problem is I have lifetime warrantys on these parts at auto zone, but these parts keep going bad. Lifetime warranty or no, it's a pain dealing with these coil issues all the time. Anyone have a better idea..? I hear about going with a different type coil.. Anyone have part numbers and where to look? Thanks...

Get refund, go Delco conversion.

_________________
~Randall~


1993 Buick Park Avenue - 197k - Some odds and ends done - Simply won't die
1994 Buick Regal - 78k - Bone stock - Always ready for a good kicking
1990 Oldsmobile 88 - Gone to a better place

OK.. What is involved in a Delco conversion? You mean an ac Delco unit? I see them at the same stores, maybe $40 more, with a one year warranty.. Are these what you mean? What is being converted if not? The coil with the three separate coils, that kind? And what about the ICM?