I had an issue with my car (1990 240)starting and then cutting off. It was doing this when i started the car and when I switched into reverse. I replaced the Air Flow Meter (used) and it seemed to work just fine. Now I am having the same problem again. It just started and I think it may have to do with the warming temperatures. When the temp dropped a fews days ago, I had no problem.

Could this be the Air Flow again? What about the cold start module?

 

Have you checked to see if any codes are logged? My guess is your timing sensor is bad of which the ECU will have hopefully stored a code and will lead you to that.