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buickguy62

ICM oozing it's gray matter, '90 Reatta

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Hi, on my '90 Reatta, which I've owned for about two months, as I was getting it ready for it's winter hibernation, I noticed the ICM is oozing some of it's gray matter--pretty positive it was not that way earlier-I would have noticed it. Now, the PO likely had some ignition issues, as included with with the car were some extra parts including a used ICM module, coil pack and used plug wires. On that coil pack was a note that one of the coils was defective. There also was some visual evidence of that ICM having also lost some gray matter. I seperated them and sure enough, there had been significant oozing from the ICM. I checked the secondary resistance on both coil packs (the one on the car and the spare one), all six coils resistered 10.5K to 10.6K ohms, OK per Ronnies Video. Looks like all the plug wires are new, the HV terminals at the coil pack are clean, as are the HV wire terminals, and the HV wires are connected to the plugs. Now I'm suspiciuous that the ICM failure is caused by some other issue causing the ICM (and maybe the coils as well to fail). It's apparent that the ICM, coil pack and plug wires all have been replaced with new.

I used my timing light to verify all the plugs are firing (at least there is 'timed' HV going out uniformly to the plugs). Car currently seems to be running good, no stumbling or roughness.

My plan is a new ICM and coil pack, but I'm concerned that I will have a repeat problem--what else should I do or check?

Thanks,

Tom

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Most likely just the nature of the ICM potting material. I replaced my oozing ICM (magnavox design) a month or so ago, and as you indicated, I had no engine performance indication of anything being wrong, I just noticed the oozing material. I installed a new ICM from PepBoys and it was potted with a different material than my original ICM (I am the original owner, so yes, I know that the oozing ICM I replaced was factory installed).

If the coil pack is failing you will notice it in the engine performance (cutting out under acceleration is one indication). The ICM's connections to the outside world are low voltage, low current sensors and outputs to the ECM and as such extremely unlikely to have any bearing on ICM lifespan. The coil pack is however intimately connected with ICM, but again, if you are not noticing anything amiss with the engine performance, not likely that the coil pack is a factor.

You can get a salvage ICM/Coilpack/mounting plate off any newer series 3800 engine and it will bolt right up and electrically connect just fine. Many have done this on this forum, as the newer Delco design is consider superior and the Magnavox design parts were hard-to-impossible to find for a period. However, I found that parts for the Magnovox now appear to be readily available. The newer, Delco design features 3 separate coil packs which does give you some flexibility in troubleshooting and replacement and it outputs a slightly hotter spark which can have positive impacts on engine performance.

David T

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Guess I am too cheap to replace a Magnavox

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I just finished replacing Magnavox coil pack and ICM, got them from Advanced Auto, pricing

BWD Ignition Control Module CBE107P - $93 use code A124

BWD Coil E45P - $38.99 using ES123

Just an FYI

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My 88 had the leaking ICM when I bought it, but it ran great. I went to the yard and picked up a Delco setup with coils and the bracket for $30.

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Way back when Magnavox was producing stereo consoles, they were labeled "Magnificent Magnavox". If you listened to the sound,

you could not help but wonder why they were tooting their own horn. Go with the Delco product, you will be better off in the long run.

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Hey now JallopyBob, Magnavox made some super nice tube stuff back 60's but they always built in a critical failure point on the component chain. For instance they used crystal cartridges on their excellent console turntables and these failed with heat and humidity after a short period of time. Maybe their ICM was built with the same logic in mind so five years later you get the oozing PCB laden potting material and need a replacement. Lots of little things like this added up to GM's bankupcy. Makes me miss the 90's. BTW: just replaced the factory coil & ICM on my 89 and it was a real mess. This probably should be on a new Reatta owner check list of things to do.

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OK. Went ahead and ordered the ICM and coil pack from Advanced Auto--they come with a lifetime guarantee, so we will see how that works, (might cover everything but oozing!! Ha.). Thanks for the discount code, gotta love this forum!!!

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Remember to save your email order receipt for proof of purchase as Advance no longer says it will keep purchase records for very long. If you do that, you should have no problem with the lifetime warranty.

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