BMW Repair: Motronic Control Unit, 1983 bmw 528e, bmw 528e

Question
I have a 1983 BMW 528e (manufacture date: 6/83) that has been completely trouble free for years. 48 hours ago, it stopped running. The engine spins, the cam spins, but there is no fire to the coil. I have replaced the coil but still not firing. There is a computer called a Motronic Control Unit located in the dash, above the glove compartment that may be the problem but as it is expensive ($1500 new) and I have no way of testing it, I am reluctant to replace it without further opinion.

Can you offer some advice?

Answer
Check the position sensor that i believe is either on the harmonic balancer or the flywheel, if it were to become unplugged the computer would not know when to spark the car and therefore not send a signal to the  coil.  Other things to check is the igniton fuse, grounds and wires.  There is no real good way to test an ECU without proper equipment but you can check the terminals and grounds without too much effort.  Does your car have the e computer? if so is it possible someone put a code in to lock the engine or does this year have that feature? i know the 85 325e has it.  If you want to talk to the real experts on this car goto:
http://www.roadfly.org/bmw/forums/
and get into the forums for your car, i'm sure they will have a few extra tidbits to suggest, you can also search the archives for someone whom has had a similar problem.
-cheers
scheidmiwa@hotmail.com