Ignition relay

[Timmaaay]

Okay, I might have an answer to my earlier question (it won't start).

Does any one have a diagram for the fuse box on an 88 M3? I'm trying to figure out which of the FIVE PRONG relays controls the ignition. Any one out there know which one?

[digdesign]

http://www.s14.net/forums/showthread...gram#post97366

Hope his helps

[Timmaaay]

hmmmm... somewhat

it shows me that at least there is no ignition relay in the main box... where could it be!?

Also, does any one know what the small 1" by 2" box mounted right next to the air box is? It's a Bosch part, the number on it is 0 280 101 001. Inside there is a circle type "contraption". Is this related to the ignition? Any takers?

[digdesign]

[m3pilot1]

pull the plastic lid. behind that you will find 3 relays.
the center relay is the one for the ECU and fuel pump.
with this relay pulled, you can crank over the engine to
build oil pressure, e.g. after engine has sat for the winter.

the sensor next to the airfilter is a pressure sensor.
the ECU uses it to make fueling and ignition timing adjustment,
in a rather rough way, based on altitude.

John

[Timmaaay]

Relay made no difference.

Crank sensors? Not sure if that s it, it runs just like a top when it does start. Once again, it only fails to start when it is hot.

Ignition control modual maybe? (It is located under the dash on the driver's side, right?)

This is really starting to get discouraging.....

[digdesign]

The symptom of a failing flywheel reference sensors is stalling/failure to start when hot.

Ignore them if you want, but it seems foolish. They're a hell of a lot cheaper than changing the ECU,.. and bad ECU's don't exibit those symptoms.

[Timmaaay]

So far, no stalling, but there is the hot start symtom. Well, in that case, this will be my next step.

One interestng thing I noticed was that the purge valve relay was wired into the main relay using c-clip wire spices.(you know, the type where you put the two wires in side by side then close the clip over them to achieve connectivity...) This did not look like something the factory would do. I disconnected them at the splices and am continuing to moniter.....

Once again, to every on out there, thanks for the help! With your continues support, and the grace of God, I will eventually beat this terrible automotivve affliction.