Greetings all.
I just recently acquired an 89 Buick Lasbre custom with a 3.8 and I'm having some issues. It has 193K on it but, starts just fine and runs (for some time) fine. The major issue I'm having is that once I've been driving for a while, she just shuts down all together. This could be while driving or at a stop light. Once I get er started back, I can rev er up and she'll backfire like crazy and the check engine light comes on as well as running rough. She drives fine after this but, the engine light stays on and has no pick up. It's kind of like it's out of time. At any rate, if anyone could help out with this, I would be grateful. I'm also having transmission slippage but, I'll get that fixed in due time as it's not real bad at this point. Thanks in adviance.

Lasabre-d00d [img]smileys/smiley2.gif[/img]

sound like it may be your ICM acting up. but first i would suggest cleaningALL connections. and read this article, it may help. http://www.bonnevilleclub.com/forum/...e=article& k=102&highlight=ground+bar

OK, first off, what the ICM? I know what the ECM is, that's the cars computer but, I've not heard of an ICM. Also, did the pontiacs and buicks have the same wiring harness in them at that time? I'm just trying to cover all the bases here b4 I go rippin stuff apart. I'm also getting some help from another forum with another car club that I belong to as well. So far, they have suggested the Coil pack (of course) the sensor under the pack and the MAF sensor. I'm still kinda trying to diagnose the problem before I break down and take it to a shop and hook it to a machine. I don't wanna spend a truck load of money trying to fix it. Anyway, thanks for the suggestion so far.

ICM is the ignition control module. it is under the coil.


and lesabre, and bonneville are they same car, for the most part. both are H body platforms. but i made the mistake of not noticing that article was for the 92-99 year H bodies. so your 89 may be different. but my suggestion of cleaning electrical connections still stands. and even if it doesnt cure the problem, it is good maintance to do. and you can check it off as a possibility.

Gotcha Sam. I've looked into the ICM and it's kinda expensive to say the least but, if that's what it is, it's a small price to pay in order to get the car running right compared to having to buy another car. I understand about doing the cleaning as well which would probably be a good idea on this one as it was sitting for some time I'm sure when I bought it. Is there any kinda of test that I can do that will tell me for sure if it is the ICM? I would like to pin it down like I said, before I go start buying stuff I don't need. Anyway, thanks Sam for all the input.

before you go to replace it, try ctaking it off, and cleaning the plate that it bolts to with a wire brush, or sand paper. and dont forget to use di-electric grease on the back before you re-install. apply liberally.


but, you can call around to local parts store to see if they will test the icm. many will. although the tests aren't 100% accurate. if it fails, then that would be an accurate test. but some can pass on the machine and still fail on the car.


i havea used icm that has just been sitting in my garage. it is good, i just upgraded to the type II with the 3 coil setup, on my park ave when i put in the s/c.

Ya got a MAF sensor layin around that's good? [img]smileys/smiley17.gif[/img] I'm thinkin that's prolly the issue.

no, not for that year. but the maf wouldn't cause the engine to shut down. it would run poorly, but not shut down, and then run fine later.





heres the icm i have, lmk if you want to try it. i will let it go for cheap.


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Ya need to take better pics..[img]smileys/smiley17.gif[/img] Thanks though. How much for just the ICM?

yeah my camera is getting old, its time for an upgrade.





you can have both for 30 bucks shipped. i would have no use for the coil, idk you may want a spare around?