Silent ICM Killer?
Thread Starter
7th Gear
Joined: Nov 2024
Posts: 7
Likes: 0
From: Oak Harbor, Wa
Silent ICM Killer?
I am confused and tired of replacing my control module every other day. I've ran into this issue like 3 weeks ago. I've replaced the Coil, rotor, New plugs(gapped to spec/0.045), and new wires(8.5mm). I've even got a whole new distributor on the way from Blueprint Engines. I've tried the AutoZone's Duralast and the O'Reilly's Standard modules and the Standard is better for it doesn't cause the car to hesitate when accelerating forward but has the tendency to hesitate whenever I'm coming from a turn( I've done a 1hr trip and made it there with 0 issues, but when I was about to return, car wouldn't start and it was a blown icm). I've checked my alternator, fuel delivery, unplugged my tach wire(which was burnt out already) and the incoming volts. The only thing I haven't yet thoroughly checked for is the grounding around the block, frame, and battery. I had assumed its my pick up coil but I've tested the ohms and its within range. I am at a complete loss and need some other ideas on what could cause this. Thank you. -79Goodday_vette
Burning Brakes
Joined: Aug 2011
Posts: 831
Likes: 288
If you already checked the alternator and the output is good , then the next thing to check would be the ground wire from the engine to the frame on the passenger side. It is notorious for corroding from the inside out.
Safety Car
Joined: May 2001
Posts: 4,757
Likes: 1,647
From: Fairfax Virginia
Die-Electric Grease is NOT Thermally Conductive like the specialized materials made for this application. I use the same material (Arctic Silver) I use when installing a new processor in my PC.
Without thermal paste the ICM will not last very long. It is critical that the surface it mounts on is absolutely clean. I wipe the surfaces down with an alcohol wipe before applying the (A tiny bit is all it takes, don't put excessive material) new heat transfer compound to the bottom of the ICM. The layer of the thermal paste should be very thin but visible on the ICM before mounting the ICM.
Without thermal paste the ICM will not last very long. It is critical that the surface it mounts on is absolutely clean. I wipe the surfaces down with an alcohol wipe before applying the (A tiny bit is all it takes, don't put excessive material) new heat transfer compound to the bottom of the ICM. The layer of the thermal paste should be very thin but visible on the ICM before mounting the ICM.
Race Director
Joined: Nov 2006
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From: Sunshine Coast, Queensland, Australia
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I'm thinking a corroded ground cable from engine block to frame as well. Worth a look. My original was badly corroded 20 years ago. Replaced it with a much heavier unit from a tractor supply. Really made a difference. Even my charging system worked better.
