Hi all,

Totally a noob-like question, but where are the ignition coils located on a 1990 300ce 24-valve? I'm sick of taking my car to the mechanic to "attempt" to diagnose my rough idle and severe hesitation problems... It definitely seems like an electrical/ignition problem and my father in law who is a good DIY mechanic agrees...

So I think I'm going to buy one ignition coil and trade it out with each of the 3 coils one at a time to see if it fixes the problem...

Can you guys tell me where they are in my car?

Thanks.

Peter

ps- plugs/wires, injectors, OVP relay, crank position sensor, MAS Control unit (which includes the fuel pump relay), 02 sensor are all new (less than 10k mi). Cleaned the ICV (which must've been replaced somewhat recently cuz it was pretty clean), mechanic claims there are no vacuum leaks. Hoses in/out of the ICV were very flexible and seemed new.

My mechanic keeps adjusting the mixture/duty cycle/etc... it helps for maybe 100 miles, then it goes back to the same old problem...

Had full valve job done with the head gasket job...

Could the ignition coils (or one of them) be to blame?

The miss occurs randomly (like a hiccup or cough) at idle in either drive or neutral. The hesitation is mostly leading up to about 2k -2.5k rpm... after that the car becomes smooth as silk, as if I flipped a switch. When it hesitates, it's almost like 1 cylinder is dropping because the rythm of the miss varies with RPM's perfectly...

I've opened the hood while it's dark to see if I can find any arcing... but I haven't had the guts to remove the air filter while running the car to see if there is any arcing under it...

Please help me. I'm about to drive this hunk of junk off a cliff.

Good news - you don't have 3 ignition coils, you have one. It is later 104 motors that went to the 3 coil setup. So your coil is at the other of the wire coming out of the center of the distributor cap. More good news - your car has a 16 pin diagnostic connector from which you can read fault codes. Try a search and learn how to build the code reader and read codes. There will most likely be good clues there.

Okay, so that is good news in one sense... that if my coil goes out, I only have to replace one. It's bad news in the sense that I had "an" ignition coil replaced about 10k miles ago, which means that my coil is probably fine.

I'll definitely search around for the code reader thing. My check engine light has been on for quite a while now...

Thanks for the help.