I've got a 90 bonneville, and it gets to the point where it wouldnt start, but just keep cranking and cranking, sputter, backfire.. and eventaully start after cranking it forever. I changed the plugs & cables and that solved the problem for 2-3 days, then the problem started happening again... I put in new plugs again, and it worked fine, then 3 days later, same thing..
crankcrankcrankcrank............. After it finally gets started it will run perfectly.. its just the starting process that is being problematic.

I replaced pretty much everything I can think of:
cam sensor, the manget (it was missing for the last year), crank sensor,
plugs/wires, checked the TPS, cleaned the IAC, new air filter, cleaned the MAF (with qd electronics cleaner, of course) & throttle body while the MAF was out. replaced the fuel pressure regulator & filter & checked the fuel pressure - turned out OK. I also replaced all my vaccuum hoses the other day (the problem existed before then, though)

Today I picked up a cheap aftermarket Magnavox-style "Wells" ignition coil at Murrays auto, and the car wouldn't even start with the Wells & brand new plugs.. Put back my old coil and it works fine (for the next 2-3 days at least). I put a special order on a new AC-Delco brand Magnavox-style ignition coil hoping that does the trick. But since i got this far without any luck at all, I am really doubting this will solve it :(

If anyone could give me some insight or ideas I would really appreciate it,
not being able to fix this is really stressing me out..

thanks
- tom

It does sound like the ignition to me. My mother-in-law'* car did the very same thing, and that'* what it was. Swapping coils should have worked though... Try wiggling the connector that attaches to it? Could be a bad connection, though that seems unlikely after swapping coils like that.

Maybe a bad engine ground? Have you actually checked the fuel pressure since replacing the regulator? Time for a new battery? Just spouting ideas here... I'm really not sure.

check your battery. there have been problems reported with these years (ive had a problem with it too today) where the battery puts enough power to crank but not start the engine

I got the new coil today & installed it in the parking lot at Murrays auto., it made my car not start at all.. I took both coils (old & new) back into murrays and talked with a couple of people and they said it was most definately the ICM, and they were right! I got the cheapo Wells ICM, ran home and installed it, now the car starts instantly, not only that, but it fixed small surges I got between 2000 - 3000 rpms, and the reaction time to stepping on the gas hard has improved bigtime as well.

btw I checked the grounds and battery before I started replacing anything.

Now all I have to do is clean my egr valve, replace the o2 sensor and figure out a way to get the white flaking clearcoat off of my roof and hood...

Your original ICM could have had a corroded or loose terminal.
Its a good idea to tighten the prongs on the connector and apply a touch of dielectric grease to the terminals.
My original ICM did the same thing and it turned out to be a loose connector with bad contacts.

Forgive me, but could someone tell me what the "ICM" is and where it'* located. I'm having problems with cold starts also and thought that may be my problem?


Thanks

Frank

Right under the coil packs. You will see a large connector with a bunch of wires coming out of it.

captainmiller

Right under the coil packs. You will see a large connector with a bunch of wires coming out of it.

Thanks for the info, isn't that called the power pack?

Frank

you have a Magnovox coil pack on top with six bolts attached to the ICM with a harness connector toward the radiator side.