Should I change ICM if I recently changed my ignition coils?

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Mar 5, 2022
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I have 2001 Pontiac grand prix GT with 117k miles, which I bought in 2011, I put 20k miles in the last 10 years. I recently changed my coils as I had intermittent stalling issues, now it works fine. Should I proactively change the ignition control module given the age? What other things I should change in my car to keep it in a good working condition? Thanks. It is a 3800 V6.
 
On a 3.8 I would recommend an ignition module at that mileage. Genuine GM or Delphi on the part. Common fail engine management parts on the 3.8s are cam sensors, MAF sensors and the odd coolant temp sensor and MAP sensor. Occasionally we would see a crank position sensor failure on the 2nd generation 3.8s but it wasnt as common as the older ones. The insulation sometimes also fails on the wiring to the cam position sensor, if thats the case the wiring can be repaired or the ignition module harness can be replaced.
 
IIRC these may be the ones mounted on a cast iron bracket and corrosion forms between the module and bracket causing the module to get hot and eventually fail. I would change it and clean the bracket well then put a coating of Arctic silver or similar compound that is used on computer CPU's on the bracketed and module. This will help with heat transfer from the module.

I use this, just use a matchbook cover to smear it thinly over the surfaces.

 
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Genuine GM ICM cost $172, which twice as much as the Delphi part $82. I thought Delphi made the GM part. There is also WVE by NTK ICM for $100, with ebay used OEM costs $35. Which is the better option?
 
Use on GM OE, spend the money once. Delphi may have made the original part but it is not the same one you would get from Rock or other aftermarket store. Forget the others, they are trouble.
 
It's not broken and you have only put 20k miles on this car in the last 10 years. If it works I would leave it alone.
 
I would not replace it, but I would do as Trav suggested, take it off, clean the mating surfaces and put down some thermallly conductive grease.

I had 3 vehicles with the 3800, none ever had the ICM fail. Putting 20K mi on it in 10 years, I can't see the benefit unless you plan on taking it on a long trip.

Other things? Just the routine stuff, check the belt and pulleys, change tranny fluid, check rust areas with risk attached like the brake lines.

If you haven't yet, you may eventually have an intake manifold leak but it is another thing I wouldn't "fix" until it needs it.
 
During the lock down time, I opened up my UIM and LIM hoping it was a plastic intake but to my disappointed it had green ac Delco metal gaskets, had to remove it and put felpro metal gaskets, I looked so dumb, because it was totally unnecessary to open up the engine.
 
I know on my 92 Cavalier with the 2.2L and the waste spark ignition, if one of the coils go bad, it usually takes out the ICM. I've owned this car since 2006 and have put several ICM's and coils in it.

The ICM prior to the one that is currently in the vehicle only lasted 11,000 miles before it went out and one of the coils was bad as well which had the same mileage. I always replace both coils and the ICM at the same time.
 
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