Hi,
Thanks for this.
The one thing we have not tried is by-passing the cutoff relay at the battery.
The suspicion is that there is a problem with a ground somewhere.
My indie thinks it might be one of the grounds that the DME needs that is not directly going to a sensor.
He has checked all the sensors and all is well there.
That is why he is now looking at the harness.
I have read many times that these cars are very fussy when it comes to the battery voltage.
I will pass this on to him and have him check it.
What he is doing now is "fooling" the ECU by simulating a very "cold" condition.
That makes it drivable but he knows it's not a "fix".
We've been working on this for over a year.

I still want to find a harness that is compatible with the Siemens DME.
It will have to be from a Euro car. The US cars use a Bosch DME. (except a few odd 320i)

Joe