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94GMC2500
02-20-2016, 15:06
I picked up a 95 K3500 last summer. When I start it to let it warm up it runs fine a little while then stops just like I turned the key off. It starts right back up. some times it will do it waiting at a stop sign. lift pump is working and tried 3 different used PMD,s on it. Any one have any ideas?

a5150nut
02-20-2016, 15:32
Were the used PMD's tested on another vehicle?

Wire connections clean and tight?

Ground wire good going to injection pump?

Are you running and extension harness or is PMD mounted to the injection pump?

If not PMD the fuel shut off solenoid would be next to check. You did say it just shuts off not die out like starving for fuel.

Have you checked fuel supply with engine running? Open the bleed valve and engine should keep running. If it stalls then check fuel lift pump in the frame rail just under drivers feet.

Robyn
02-20-2016, 18:38
Stalling after any reasonable run time (longer than a minute or so) is very very likely a bad PMD.

Could be an optical sensor, but I would get a new PMD

I will get some flak here, but go with a DTECH PMD and mount it on a remote cooler.

Be sure to install the correct resistor in the PMD PLUG POCKET ON THE PMD

If you don't know what # it was fitted with, then use a #5

The resistor that is in the one that came with the truck can be coaxed out carefully using a piece of welding wire with a little hook on the end and grabbing the small holes in the resistor one at a time and wiggling it up and out.

The resistor is shaped like the socket and is about 1/16" thick or so.
It slides down over the pins in the socket.

Use a good remote mount that is not under the hood.

The forward aluminum skid pan is perfect.
Mount the cooler on the inside of the pan, connect the extension harness and plug the extension into the engines PMD harness.

Leave the ground from the PMD harness fastened to the IP as factory.

Good luck.

94GMC2500
02-23-2016, 09:21
The PMD,s are all used. I don't have any way to test them. The PMD is mounted behind the front bumper by the opening in the bumper, I don't really like it there. I got a couple extra injection pumps with the truck, I am going to try switching the fuel shut off for the heck of it. My truck don't have a aluminum pan under the front, maybe its missing.

94GMC2500
02-23-2016, 12:37
I put a different shut off valve in it today and so far it has not stalled. but it would not do it all the time. One of the PMD,s I had on the truck totally died today. I have 4 other PMD,s that all start and run. I guess I will just have to see if its ok now. Also I looked today and didn't find a ground wire from engine to the cab, maybe that is part of the problem.