Died while driving, won't start and stay running now

[opethmike]

A few days ago, while idling in my drive-way, the DeLorean stopped running. I was able to start it right back up again, and didn't give it a second thought.

A few hours ago, while driving away from my house, the car died, so I coasted to the side of the road. Turning the key, it would crank, and fire very quickly, but would die right away.

One interesting thing that I noticed is that if I held the key in the start position (kept turning the starter), the car would keep running. As soon as I let go, car would die. Had to have the stupid thing towed back to my house.

Please advise as to where I should start my diagnostics.

[ccurzio]

Having just experienced similar symptoms rather recently, check your fuel system. When was your fuel filter last replaced? How's your pump?

[opethmike]

Fuel filter replaced this past January. I'll check the pump tomorrow; I tried swapping RPM relays, but that didn't help. How do I use my multimeter to check the pump?

[ccurzio]

Fuel filter should be all right then, unless some massive amount of gunk somehow got displaced and lodged itself in there recently. Not likely.

Try pulling the plug from the warm-up regulator and sticking it on the cold-start valve and see if your engine starts that way. (Open the engine bay and pull the gray plug out from the forward driver-side of the engine compartment, then pull the blue plug off which is slightly above and closer to the rear of the vehicle in the same area, then put the gray plug where the blue one was.) Don't run this way for too long, just see if it gets going.

[DeLorean03]

He cant do that. He's running EFI. It says so in his signature and avatar quote.

[AdmiralSenn]

Mike, I posted this on Facebook but I'll post it here too for future thread-hunters.

I had this EXACT same problem a long time ago and wasted a lot of time checking the fuel pump circuit.

The fact that it depends on the position of the key is your big clue - this is an electrical problem. In my case something had bumped one of the wires loose on either the main or auxiliary relay (I forget which) and it would only pass current in Start, not Run. I tightened the offending terminal (and the others too as a precaution) and it worked beautifully afterwards.

The only other thing I can think of is something wrong in the ignition switch - same circuit.

[ccurzio]

He cant do that. He's running EFI. It says so in his signature and avatar quote.

I didn't see this. I pay attention to usernames and post content/context, and ignore signatures and avatars.