OK i have a 92 Regal with a 3.1 and Auto trans...A/C Power doors, locks. Unknown Miles as the OD does not work but the MPH does.

Car would run for a bit then die. Would not restart for 10 min, then would restart and run ok for some time. Or it would run rough and die out again. Replaced Fuel Filter.

Took to the dealer in town. First thing they said it was the IAC as the pintel was broken. Then they said it was the crankshaft sensor. Replaced both and did relearn at the shop. When I take it home two days later does the same thing and will not restart after shut down. They bumped up the idle a bit and this seemed to help They also tested the fuel rail and was at 44 psi if I remember right. All this time the car runs smooth and the shop can not dupalcate the dieing. The next day the car dies again and will not restart for 15min, I pull out a plug wire and ground it, no spark.

So I remove the Spark control modual and it tests ok cold at autozone but replace it anyway. test coils middle one is at 11k ohms replace that too.

Start the car up and it does run but has bad misses and studdering. swap positions of coils no better. take back to shop and have another relearn done, this does not help. Shop says to try and find another ECM. I do, same problem. Still no codes after 15 min of driving.

How long does it take for an ECM to learn after replacing them, how am i suppose to drive it to make it learn.

The way it is runing now is not how it ran before I started repairing it, so I dought that the wire or plugs have gone bad in this time. From the book I do have the wires plugged correctly to spark plugs.

Any ideas as to where to look at next.

Also after i turn the key off there seems to be a more prounced vacume let down somewhere near the throddle body, seems to be coming from within the engine itself. If this helps.

Thank you

Have you (or your mechanic) checked the ECM, ICM and crank sensor wiring harnesses? These cars are common problems as these cars get older. Corrosion and abrasion can cause all kinds of start/no-start issues.

the Crank sen is new and so is the harness per the dealership. Ran smooth but would die after replacing this.

I have swapped out the ECM( black computer under the over flow tank) still runs poorly.

ICM???? I take that as the Ignition Control Modual( Has 3 coils mounted to it). Replaced that and that was the first time it ran bad. Swaped it back to the old unit and it still ran bad. Hmhm may see a problem here. Might have gunk, for lack of a proper word in the harness. Car is oily.

Ill go and check the 3 wire harnesses that attach to it.

Thanks for the reply.

Richard

you are correct, ICM = Ignition Control Module.

Check all the small pins that are inside the ICM and the female spade connectors in the vehicle harness. It's highly possible one either bent or may have corroded and fallen off and is stuck in the vehicle connector. It's a 14 pin connector (7 pins on each side of the center bolt that holds it on) and they should all be used (no gaps or missing wires/pins).

I guess I should update this, turns out I forgot about KISS Keep It Simple Stupid, it seems that I had #3 and 5 spark plug wire crossed.

now it runs great and so far no more dieing

Thanks for your replies