Once engine is hot, backfires, stalls, stops

[Rob Bell]

Re: Once engine is hot, backfires, stalls, stops

I'm thinking that the ICM is causing misfires which could be stuttering, hesitation, bucking, running rough, and maybe even backfires if enough unburnt fuel is getting into the exhaust system. His symptoms sound kinda similar to how my cars behaved when their ICM's went out. They had no problem starting, but boy when they got warmed up the fun began.

Another thing I've noticed from experience, is that bad ICM's don't seem to throw codes. I think it's because the ICM is what tells the PCM when something is wrong. But if it's the ICM itself, it doesn't know there's a problem. It doesn't want to narc on itself.

[ssms5411]

Re: Once engine is hot, backfires, stalls, stops

I had ICM go out before but it would through SES light, but also PCM might be going bad an maybe injector or 2, need to scan it. I would think there woul be stored codes somewhere unless the mechanic wants to make a buck. Which I have seen.

[Blizzard242]

Re: Once engine is hot, backfires, stalls, stops

I had ICM go out before but it would through SES light, but also PCM might be going bad an maybe injector or 2, need to scan it. I would think there woul be stored codes somewhere unless the mechanic wants to make a buck. Which I have seen.

X2

However, if for whatever reason it maybe, if the SES light isn't coming on it wouldn't hurt to have the ICM and/or coils checked for free anyways.

[Rob Bell]

Re: Once engine is hot, backfires, stalls, stops

Oh I agree, definitely get it scanned first before doing anything else. Don't just tear into it or throw money at it. If there are no codes, then start taking things in for testing. Luckily, testing is free. And ICM's aren't horrendously expensive if it does end up being that. Not really cheap, but it won't bankrupt you.

[Leonard 3.8L]

Re: Once engine is hot, backfires, stalls, stops

ICMs are usally an easy fix.