PontiacBonnevilleClub.com

1989 bonneville. At around 120k the factor ICM went south along with coil pack. Since then I've been thru 2 more ICM and another set of coils. In the last 50000 miles.

What could be causing this? I seem to recall someone here talking about the ICM itself doesn't hold up well to heat. The Magnavox style system. But: either I'm getting a bunch of junk parts OR something else has to be causing this.

Also, IF I recall correctly I read something about putting di-electric grease between the module and the mounting plate. However,
the Factory Service Manual says nothing about that under the reassembly instructions.

Frustrating.

Thanks!

From what I understand, the Magnavox type system as a whole was junk, prone to failure, and requiring complete replacement when it does. Most switch over to the newer Delco system, and never look back.

Also, if your alternator is letting too much Alternating current into the electrical system, it can also contribute to module failures, especially the ICM.

RJolly87 wrote:From what I understand, the Magnavox type system as a whole was junk, prone to failure, and requiring complete replacement when it does. Most switch over to the newer Delco system, and never look back.

Also, if your alternator is letting too much Alternating current into the electrical system, it can also contribute to module failures, especially the ICM.

I'd love to be able to find VIN L engine to swap it over, but have had no luck so far.

Also, it sounds like the BWD coils are junk. The ohm out high perhaps.

Why do you have to find an engine? I got the bracket and everything off of ebay.

You do want to put a liberal amount of dielectric grease under the ICM. It helps maintain proper grounding and heat dissipation. And obviously, you want to clean the contact area before applying the grease.

You can try car-part.com for the bracket to swap over if you are having trouble finding one at local yards.