Pontiac Repair: 2002 Grand AM Misfire, ac delco, liter engine

Question
QUESTION: I have a 2002 Grand AM with the 4-cylinder engine.  A month ago I experienced a random misfire code P0300.  The shop I took it into replace the ignition coil and the ignition control module.  2 weeks later I had the same exact problem and they replaced the ignition control module again under warranty saying it had failed.  Now almost a month later the same exact problem has happened again with the random misfire.  Is it possible the ignition control module failed 3 time in a month and a half?  Any insight you can give me is greatly appreciated.

ANSWER: Hi Eric:

does this have a 2.2 liter engine? That has one big coil assembly that runs all 4 cylinders. Thsy do go bad quite often but not 3 times in a month. Same with the ignition modules. If they are using after market parts I would suspect maybe sub par parts.. The other thing could be spark plug boots or plugs. If this only misfires when cold and damp that is the first thing I would look into. The boots are what connects the coils to the spark plugs if this car has a lot of miles on it the boots can go bad and they start to "leak" voltage and misfire. The damp conditions make it easier for the spark to jump a gap outside the engine that the gap under compression inside the combustion chanber in the engine. If it does it long enough the plugs will get what is called carbon tracking. And what happens is that carbon tracking is easier for the coiuld to fire that gap then the plugs and the engine starts to misfire. That is what I would look at first and foremost. Good luck :)


---------- FOLLOW-UP ----------

QUESTION: Oddly enough I was doing some more research last night and found that on this 2.2 liter engine using multi-tipped spark plugs could cause the ICM to fail.  Before I had the three failures, I had installed the quad tipped plugs from bosch because the AC-Delco plugs were not available.  I replaced the ICM and installed new AC Delco plugs and it cleared up all my problems.  The only thing I can think of is too much resistance with the multi-tipped plugs causing the ICM to fail.

Thanks for all your help.

Eric

Answer
Your welcome.

Your one to something with that. Magic spark plugs do not work! If they did the factory would used them right from the get go. I'm a firm beliver that you install the same parts in the cra that came with it from the factory! Gm use only GM parts Chrysler use only Mopar etc...