[JK McDonald]

Hey John - Since you mentioned that you'd bench checked the AFM - were you able to determine if the AFM wiring harness and pin numbers checked out OK back to the computer connector ? It sounds like you may be looking for a pin out error or a short to ground that kills the computer when the AFM is connected.

I was talking about your lack of the injector ground pulses when the AFM was connected with a retired BMW service tech. Even he said this was a strange symptom if the interconnecting wiring harness is good. One of the things he remembered was that the BOSCH L-Jet computer P/N's and the AFM P/N's were normally a matched set. It's not that they couldn't be interchanged between series numbers IF the In/Out pins were verified to be compatible. It was just that the performance of the car may be off a bit. He also said the early L-Jet computers were designed to control either high or low impedance injectors - and the injectors were not interchangeable. The difference is in the match of the output circuitry and the overall shape of the ground pulse to each type (High or Low) impedance injector. There is something different in the leading edge of the start and taper of the holding current sent to the injectors to prevent over heating of the computer driver transistors.

I'm sorry to say that I've not been able to turn up a computer to send you and help in your troubleshooting effort. Perhaps you could ask the previous owner what brought on his original problem and what he did that caused the car to be parked ?

Michael