In my case, the 1992 300E, it is apparently the safety switch that is bad. It sometimes, not always, stays open when it should close, which means it incorrectly shuts off the fuel pumps and causes engine to stall. It is temperature related, only happens when engine is cold and warming up, not when it is at full operating temperature.
And I am told it will be something in the order of $1500 (part and labor) to fix, all for a switch that probably would cost $10 or so if sold separately. Aggravating!
1992 300E with ASR
35 years of Diesels until now!