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!
Multiple ICM failures...what is going on?
- RJolly87
- Certified Bonneville Nut

- Posts: 5403
- Joined: Tue May 27, 2008 8:53 am
- Year and Trim: 1993 Buick Park Avenue
1994 Buick Regal Custom - Location: Las Cruces, NM
Re: Multiple ICM failures...what is going on?
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.
Also, if your alternator is letting too much Alternating current into the electrical system, it can also contribute to module failures, especially the ICM.
~Randall~


1993 Buick Park Avenue - 197k - Some odds and ends done - Simply won't die
1994 Buick Regal - 78k - Bone stock - Always ready for a good kicking
1990 Oldsmobile 88 - Gone to a better place


1993 Buick Park Avenue - 197k - Some odds and ends done - Simply won't die
1994 Buick Regal - 78k - Bone stock - Always ready for a good kicking
1990 Oldsmobile 88 - Gone to a better place
Re: Multiple ICM failures...what is going on?
I'd love to be able to find VIN L engine to swap it over, but have had no luck so far.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.
Also, it sounds like the BWD coils are junk. The ohm out high perhaps.
-
Keepin'her_going
- SLE Member

- Posts: 68
- Joined: Tue Jul 29, 2014 10:36 pm
- Year and Trim: 1991 Bonneville LE
Re: Multiple ICM failures...what is going on?
Why do you have to find an engine? I got the bracket and everything off of ebay.
- Wes
- Posts like a Northstar

- Posts: 2363
- Joined: Thu May 22, 2008 8:09 pm
- Year and Trim: 2002 Buick Park Ave
- Location: Michigan
Re: Multiple ICM failures...what is going on?
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.
You can try car-part.com for the bracket to swap over if you are having trouble finding one at local yards.

92 Olds 98. L67, Gen 3 M62, 2.55 pulley, FWI, PLIM, 1.8 YTs.
yourgrandma wrote:High


