BMW Repair: tachometer/speedometer/not starting, electrical pulse, position sensor

Question
89 525i - the tach and speedometer had been acting up for 2 weeks, either not working or showing higher values than they should, then it started twice and ran for 10 seconds then died,now it won't start at all, i think the battery is good, any clues ?   thanks,  Steve

Answer
Stephen, I have very little experience with this year/model. Your question is better posed to one of the older experts. I believe that the DME is missing an input for for injection/ignition. I would look for a loss of ignition spark or fuel injection electrical pulse from the DME. Inspect the crank position sensor and pulse wheel. Good luck.
-Evan