I have a 1997 6.5 turbo that occasionally won't start unless I pull fuse 6B, the fuse isn't blown. The fuel pump won't run, pull fuse and reinstall and it will start up. It will do this occasionally while driving as well. Curious if this is a ECM issue.

 

It doesn't seem to be a PMD issue. It has the relocate and it will do while stone cold in the morning.

 

Have you checked the grounds and harness to the lift pump? Is the canister full of fuel?

 

Could be the electronic shut off solenoid on injection pump. That fuse is a feed for it. Might be resetting it when removing the fuse

 

If you had a short to ground on the control side of the circuit that would energize the solenoid and shut off fuel. Or the pcm is commanding it closed. Or the solenoid is faulty.

 

I would check all ground wires you can find, there are some on the intake manafold studs. Is the truck stock ir do you have a aftermarket alarm system? When removing and reinstalling the fuse it sounds like you are reseting a relay. Where are you located?

 

When you say it "occasionally won't start unless I pull fuse 6B, the fuse isn't blown"......I need more info. Is the engine turning over and won't start or not cranking over? If it's turning over but not starting does it puff white smoke from the exhaust or not? If it does it's probably fuel related, if it doesn't it's probably electrical because you said it does run sometimes and if you pull that fuse.

The grounds on the back of the aluminum intake manifolds is the direct ground for 2-3 circuits directly from the ECU. In the statement above when I said "electrical" that could be all sorts of things from wiring to ECU, PMD, IP FSS (should be called "run solenoid"), ignition switch (I've seen that happen but I'll spare you of the long explanation). All of these things would cause it to not start and not puff white smoke while trying to start. If you have white smoke puffing you're chasing down something completely different than if you do puff smoke.

 

I’m having similar problem: she starts just fine but after driving her & she gets hot, I turn her off & she won’t turn over again until she cools off.

Everything pointed to PMD but I just replaced it (literally).

Im going to try the 6B fuse tomorrow and report back but any other suggestions would be greatly appreciated!

Free beer for the one who figures it out. cheers!