1997 6.5l issues

I guess I keep forgetting things. The fuel tank is 2 years old. New sending unit. New fuel lines at the rear half.

Yes it will restart and idle fine, but as soon as you give it throttle it will die again.

It does this only after 15+ miles of driving in town. The PMD is so hot you can't touch it so the owner said. I'm a good 1/2 hour away from him and can't find the time to get out there, so he hasn't been driving it.
 
Get the relocation kit that moves the PMD down to the bumper or elsewhere away from the engine compartment. Might check the resistor in the plug also.
 
^ thanks for the reply, but for the third time..lol. The PMD is a new D-Tech and has been relocated since I put the injection pump on in februrary. Not trying to be a d¡ck, but in the first three of my post states everything that I replaced or is new to the truck. I do apriciate all your replies.
 
I know it's new but still it's in the engine compartment and electronics hate heat. That is why I suggest the other relocation kit
 
Ok, I understand where your coming from now. I called the company and they told me to double check my timing first. That if its too retarded it can cause some issues.
 
That can cause issues depending on how far it's off. It's worth a try. That will help eliminate another possibility.
 
So The issue is fuel related. I wired the lift pump directly to the battery and fixed three minor leaks around the gauge. The engine starts up and has 7psi of fuel pressure running. After five miles up the road it starts cutting out and I pop the hood and read 0psi. I take the fuel pressure gauge off the valve to see if fuel is coming out and after 2-4seconds fuel will come out. Put the gauge back on and working 100yards no fuel pressure.

I think air has to be entering the system and causing the fuel pump to lose prime. What's your opinion. I really only have a good 1hour max to work on it in a week.
 
Is the gauge before or after the filter? Maybe something is in the filter plugging it up. Does the pump quit when you have this issue after the hot wire? I can't remember if they shut of after building so much pressure or continue to run.
 
The fuel pressure gauge is on the valve. The lift pump is still running and hot wired straight to battery(for diagnostic purposes). It's had 2 fuel filters recently and 2 H1 Lift pumps.
 
The next step is to put a vacuum guage inline before the pump and see if it is getting vacuum at the pump pickup. If there is no vacuum there, then chences are you have a kinked hose that folds over when it gets hot. A known area to check for fuel line kinks is under the fuel filter manager. There are a few spots where it loops around and can kink over and cut the fuel supply off.
 
Alright, so we drove it up the road to where is was acting up and began inspection all rubber hoses. It felt and appeared that no hose was collapsed or soft and no cracks present. So we decided to drop the fuel tank for the third time and inspect and test everything. Removed the sending unit and pressure tested for leaks. That passed inspection but measured to sit 1 1/4" above the tank bottom. So I bent down the pick to 1/2" off bottom. Found three o-rings that appears to be hard, but not cracked. Also I wan to note, the fuel tank does not have a bladder in it, just a steel tank with a baffle around the pick-up. Pressure trees the lines and all passed. Put it back together and drove about 3 miles and fuel pressure remained 6psi while idleing and drove perfectly. Put on another 10 miles last night and it didn't act up once. We did put another 1/4 tank of fuel in so we now have 1/2 tank.
 
Maybe that was part of the problem not getting to all the fuel in the tank. Did it always act up that low or did it do it even on a full tank?
 
Alright, I am so sick of this truck. The H1 ACDelco pump seemed to take a dump. It seamed as if once the pump got hot, it stopped working. Let truck cool down and fuel pump create pressure again. Swapped it out with a Delphi pump and same thing, but less initial pressure. So I figured I would try another method. I used a 99+ Powerstroke Fuel Pump(50psi) with a regulated return. Got it don't today and I worked great for about 10 miles then its like the fuel pump got shut off and fuel pressure went to zero, shut engine off and it hopps back up. Start engine and fuel pressure goes back to zero. Let engine cool and it works normal.

What's going one?
 
It's been a while since I dealt with mine and can't remember if there is a relay in the system or not. Might check that or try a higher amp one.
 
Nothing wrong with electronics. ECM has commanded lift pump on and i get full voltage at pump. As of now, the pump is wired direct when this happens.
 
You might have full voltage at the pump but running too many amps through it causing it to get hot. I wouldn't rule electrical completely out of the question.
 
There is nothing wrong with the fuel pump, but I think I found my problem. There is a baffle/bowl that the sending unit sits in. It's spot welded to the bottom of the tank, but there is no way for fuel to enter the bowl quick enough below half tank. I found this out hole installing a sump in the bottom of the tank.
 
Fixed the truck back in late July. Ended up installing a sump with a Powerstroke electric fuel pump plumbed inline with a regulated return system. It seemed to pick up some power and holds a steady 6psi fuel pressure on wot run.
 
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