83 733i wont start

[pakrat]

Help. What happend? My car was running fine one day, afew days later it would not start. I checked the most commen items and found nothing, but when i checked to see if i was getting fire i found that i was not. Assuming that the problem was in the coil , i replaced it. Once done again checked for spark, it was there, but when i tried to start the car still nothing. Back tracking i checked agian for spark, nothing.Does anyone know where my problem might be??????
Please help. very sressed

[jeffreyb4me]

There are many possibilities BUT the most likely, easiest and cheapest would be to [test first if you can] replace the MAIN and FUEL PUMP Relays. The MAIN is usually the culprit but they both age. They're clipped onto the outside of the fusebox. The MAIN has 5 pins with 2 fat RED wires to one of the pins, 2 fat RED/WHITE going to another. The FUEL PUMP relay has 4 pins with 2 GREEN/PURPLE wires coming off one of the pins. The MAIN powers the DME with the key on, the PUMP is powered during cranking or running only..........................jb.

last thought for clairity.....the coil IS NOT powered [B+] by the DME Relay. that B+ to 'power' the coil comes from the ogn. switch. The coil is GROUNDED [controlled] though by the DME Control Unit [ Powered by the DME Relay ] i.e...no spark, no injection signal either [usually].....jb.