1990 e350 460 e4od. Lately driving around regardless of whether the ambient temp. is hot or cold, or regardless if I've been driving for hours, or right after start up, the engine will sputter, then die. Then I can start it right up, and it could be 2 seconds later and it will die then I can start it right back up... I just changed the ignition coil, control module, cleaned all air filters, and cleaned pcv. I originally thought it was vapor lock, but early this morning I was taking it to get smogged and it sputtered then died at a light, I turned her right back over and she died again. I turned her right back over again, and while driving she was starting to lose it again , I have her some gas and kinda woke her up, and I decided to pull into the mechanic. Well, she sat at the mechanic ALL day today and he couldet find anything wrong. No codes, nothing. It's almost like i have a ghist problem. Wtf!?

 

Get a fuel pressure gauge and monitor fuel pressure while it's running. Sounds like it could be a failing fuel pump.