Hi - I'm new to this forum and there'* some great info posted here. My son'* '88 Bonneville had been giving him problems recently - he told me that he'd be driving it and the engine would quit. Sometimes it would restart right away, other times he couldn't get it going. Well, it always started and ran fine for me, so I wasn't sure what the problem was. Last night I took it for a drive and the engine quit on me - just stopped running and all of the indicator lights came on. Now it won't restart - it cranks fine but doesn't even cough. I haven't had a chance to attempt to diagnose it yet, but I'm thinking bad ICM, CPS or ECM. I've read that it'* difficult to bench test a CPS and that a bad CPS will prevent the ICM from firing the coils, causing one to possibly suspect the ICM. Is there a way to eliminate one of these as the cause? Car ran great up until last night.

Thanks,
Jim

It'* a C code motor with 180K. It ran really well until it quit. I had an '89 GMC Jimmy with the 5.7L that did this with a bad ICM. That had a distributor though.

Thanks,
Jim

Crank sensor, Ignition Control Module, fuel pump, ground bus & poor battery connections can all cause stalling. Start by cleaning the battery cable terminals & then check for spark at each of the three front cylinders. Let us know what you find.

I had the exact same thing happen to my 88 SE.

If you take the coil pack (the square Magnovox type) off the module., the computer board should be completely sealed over with a resin epoxy type material. It should be hard and completely smooth. If it is sticky and bubbly lookin, it has gotten too hot and is probably burnt up or on its way to being fried out.

If this is the case, which I would bet the farm on it is, save yourself a lot of headaches and go buy a brand new one at Auto Zone for 180 bucks.. I first tried the delco coil pack swap (twice) and it did not work and then bought a Magnovox from a junk yard for 35 bucks that went out 6 months later.

Been away for a while, but I wanted to let everyone know that a new crank sensor took care of the problem. Starts and runs fine now.

Thanks,
Jim