My ICM's only last 2-3 months!

[John Deere Boy]

This is in an 88 olds cutlass ciera, 2.8L. We've replaced the crank sensor and coils, used dielectric grease all around the modules, and cleaned all the connections, but this thing still keeps blowing ignition modules every couple months or so. We've tried Autozone ICMs and Carquest ICMs with no luck. I just spent an hour searching this forum and found that some people are relocating the module away from the headers. Is this what i need to do, or is there something else that is frying it?

[3100 MPFI]

if it is just the coils frying, I would start thinking something was wrong with the DIS itself. If it was me, I would put a new DIS on there, and get some GM coils (they last longer than aftermarket ones anyways).

That is what I would start with.

[John Deere Boy]

By DIS, do you mean the ignition control module ( the plate that the coils attach to?)

If so, that's the part that keeps blowing. We replaced the coils thinking one of them might have been frying the module, but that was not the case.

[IsaacHayes]

When clicking this thread I thought "I bet he is using Autozone Parts"....

#1, get a different CPS other than Autozone. See if it fixes it. Then if not put back on the old ICM or a different brand other than Autozone.


I replaced my CPS with an autozone one and it crapped out a few months later. I thought it was the ICM because I had just replaced the CPS. Spent $90 on a new ICM and no dice. Then I wised up that the CPS I got from autozone was bad (only part I got from there.) talked to others who have the same problems with autozone electronics.

[John Deere Boy]

It is a Carquest CPS with Carquest Coils and a Carquest ignition module. We stopped using autozone parts after the third or fourth module. But a carquest CPS could fail too...perhaps i should replace it again?

(i don't like autozone parts either, but an autozone ignition module has been in my bonneville for six years. they do work sometimes)

[SappySE107]

It shouldn't die that fast from the manifold heat. I would check your grounds and the bolts/threads that hold the ground rings to the block. Just a guess of course.

[IsaacHayes]

No experience with carquest. No idea where they get their parts from. But yeah if it's not crappy parts there is something else killing them like a bad ground.

[IanSzgatti]

check the icm fuse port and see how much amperage it's drawing... cehck all grounds.

[merlot566jka]

check your plug wires and see if they're grounding out

make sure you have no oil or water leaks in the area

relocate the icm and coil packs, use 3800 plug wires to reach the new location

again check grounds


i went through teh same thing years ago with an 88 z24. once i relocated the coil packs and icm and got new plug wires it lasted a very long time.

[John Deere Boy]

Well we had the ICM replaced under warranty, didn't fix the problem. So I went back and got a crank sensor....still no dice. So returned the ICM AGAIN and voila....runnin like new. The new bad one tested good several times on Autozone's fantastic tester. (Yes i had autozone replace it the second time since we struck out at carquest, and we have receipts from each store) I swear these aftermarket ignition modules are completely worthless.

Dad cleaned the grounds, again, and we threw in new wires for good measure, but Dad decided not to relocate the module and coil pack since we both figured heat alone wouldn't blow these things in two months or everyone would be having trouble.

[IsaacHayes]

Odd, the one on my car when I bought it was aftermarket, works fine, so did the $80-90 one I bought when the CPS went bad and I didn't know it... I have 2 spare ICM's that work that have been on my car on-off lol.

Make sure they are grounded well with the bolts and that it touches the aluminum plate well... it acts as a heatsink (yeah bolt to a hot motor but still).

[John Deere Boy]

Yeah an aftermarket module has been on my bonneville for several years. I wish it was the one in the bonneville that kept goin bad because you can get it off in a minute or two. I love 3800's