I have a 1985 528e. Had the car garaged over the winter and drove it a few times in winter and now in spring. Tried starting, no luck. Put on a trickle sharge, car started up and I was able to drive it a few miles. Now, the car won't start. Everything electricla is working. Ideas - main relay? Fuel pump relay? Any help is appreciated.
The battery may just be too weak to crank the car after sitting all winter. Try jump starting it and see what happens. If that doesn't work, report back and I'll see if I can get it figured out with you. You can also check out MyE28.com. Out of curiosity, when was the timing belt done last?
Re: 1985 528 will not start I have had the car on a charger. Still no dice with starting. Today, I will replace new relays (main ecu and fuel pump) to see if that works. I will keep you updated.
Timing belt Timing belt was done in 2006, but not many miles since it was changed. I was out of the country for over a year and I also drive 3 other cars.
It is a good idea to replace it soon just because of the age. At any rate, if it does not crank, it is not the relays. If it cranks and does not start, it could be. If replacing the relays doesn't fix it you can try jumping out the relays which might help point to an issue with the circuits that control the relays. Does the car have the on board computer or just the multifunction clock? Is the car an auto or manual?
Ecu It has the ECU. I see what you are saying about the timing belt because of age. The car is automatic. Could it be ignition related too?
Does it crank but not start or no crank? I'm not talking about the ECU (engine computer), I'm talking about the display just to the right of the instrument cluster. Is that a 6 button clock or a 13 button on trip computer?
The main and fuel pump relays have absolutely nothing to do with it not cranking. Now here are some things to try: Measure battery voltage with key off, key on, and key in start position. Key off should be above 12.5. Key on may dip to low 12s. While trying to crank it should not dip below 10V. If when you try to crank the battery voltage does not dip at all you either have an ignition switch issue or a starter interlock relay/neutral safety switch issue. Try starting it in neutral. report back.
Sorry about long delay in answering. It was the ignition switch. It finally crapped out after 26 years.