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[Hopyardboy]

My '86 325es won't start. I went through the Bentley's manual and have determined there is no spark signal from the Motronic computer. The Main relay & Fuel Pump relay check good but I don't hear the pump run. I did the Motronic checks in the Bentley manual (disconect plug and jumper the connections) and the fuel pump relay control is ok and pump runs, the speed and reference sensors are 950 ohms, the power and ground is where it should be, fuel injector control works, coolent temp. sensor is 3Kohm, and air flow sensor fluctuates when engine is turned over. So it appears that the Motronic unit is not sending the appropriate spark and fuel pump signals. Did I overlook anything? How about the OBC Code disable? I don't use it but is there a relay that could be bad, telling the Motronic computer not to start? Anybody know what the reference and speed sensor signals are supposed to look like when the engine turns over? Any other suggestions?

[Ken Juul]

If the car was running and now it is not, I would guess that something is not making contact. I think I would clean and tighten all the grounds and clean all the connection plugs associated with engine control. I remember reading about one buryed under the intake manifold that can cause a myriad of problems. There was also something about the alternator ground wire being disconnected. Can't remember if it was a charging problem or the car not running right. Chasing electrical problems is probably the most frustrating maintenance task. Good luck

[ptrau]

I read your post and don't know if you have checked the timing belt. You said there is no spark. If the timing belt breaks, the engine will turn over but you will not get any spark from the distributor.....distributor will not be rotating. I chased a problem on my daughters car for a day and a half 2 years ago and this was the culprit. For your sake....I hope it's something electrical.