I have a 1986 190e 2.3 that has a strange problem. (Gremlins I suppose) The car was running fine and then all of a sudden it started to die intermittently. Let it set a few minutes and it would start again. Replaced the following: 1. fuel filter, 2. Fuel pump relay, 3. OVP After replacing OVP, car ran well for about 100 miles. no stall, no die, etc... and then all of a sudden it started it again. I have noticed before it dies that the tach kind of goes erratic!! When it stalls I can crank engine and it will run about 5 seconds, enough to get it off the road!!! This is very frustrating!
Could this possibly be some sort of vacum leak or maybe losing ground in the wiring? I do hear something under the dash like a heater vent or air vent or something with a flapper closing when I let off the accelerator but I dont think this has anything to do with my problem as the car has done this since I got it. Please help. Any suggestions would be appreciated. I am to the point of basically selling the car for salvage if I cant find the problem. I am not going to drive anything that I cant rely on.

Thanks

1980 450SL (best car I ever owned)
1983 380SEL (very comfortable ride)
1986 190-E (not for long)