2003 BMW Z4 stops running

[jimgilbert]

My Z4 has developed a problem that the dealer can't solve. There is reference to this issue on the internet, but I have found no solution.
On a recent trip (400 miles) the engine quit running as if the switch was turned off. No engine warning light. Just quit. It restarted after a couple of minutes and I continued with no other trouble.

Last week on a 50 mile drive it quit 4 times. Now I can't get out of my drive.

I have checked the fuel rail and it's fully primed with fuel. Pressing on the Schrader valve will cause fuel to hit the opened hood. There is no check engine light on, but I replaced the crankshaft sensor anyway.

There is a number of faults in the internet that seem to be related to a software fix for the DME, but my car has the latest software from 2007.

Any help appreciated.