[Don Plumley]

Thanks Johnny - also posted on the question on bimmerforums.

Update:

For grins, replaced the DME/Main relay. No Joy.
Tested the reference sensor, resistance within spec.
Disconnected the DME connector. The pin-outs were not corresponding to my Bentley, so I simply reconnected it.

And the car starts!?!?!

Okay, so that's good. But worrysome that reconnecting the DME harness "fixed" the problem.

But now, when you blip the throttle, the engine rpms drop and then stumbles. Idle Air Stabilizer valve? I cleaned it out a bit, no real change.

More confused now as to why the car wouldn't start, and now does...