Starts, dies, restarts fine diagnosing

[AnonEd]

Asking for pal with 1994 4x4 2500 manual (3.55:1), 200K miles, completely stock driveline and fuel system. Have tried new search function but can not find exactly what I'm looking for...any/all suggestions welcome.

Occasionally truck will start, run a couple of seconds and die. It restarts just fine and stays running normally. Problem can not be correlated to hot or cold start, any climate condition, fuel level or pump source, truck attitude or anything else...after six months of tracking it remains completely random. The plunger appears to be moving normally, and apart from this truck runs just like it always has.

TIA for help or thread links.

 

[GAmes]

What is the idle speed after the engine is at normal operating temp?

 

[hcole]

I would check the connector on the fuel solenoid on the P7100. There are 3 wires, 1 for pull in, another for holding the plunger and a ground wire. the hold wire or ground could be loose or corroded.

 

[AnonEd]

Normal op temp idle speed is 750, about what it's been since purchase in the '90's. Wire checking ordered.

 

[GAmes]

Normal op temp idle speed is 750....

With or without the AC on? Should be 780 in neutral, AC on. I have mine set to about 850 for two reasons. More cooling in the summer while in traffic, higher RPM when cold in the winter.

 

[DonFitzwater]

Use some heavy zip ties and lock the fuel shutoff in the run position. If the problem goes away, it’s just a problem with the shutoff/run system.