96 PSD acting up- a little help please

[superduty4x4]

I'm trying to help someone get there truck back up and running. The guy called me and said it would start, run for about 30 seconds, then sputter and die. I took a look at it and hooked it up to AE, everything checked out fine but the ICP was all over the place, so I swapped the IPR with my spare and she lit off and ran like a champ. It needed a glow plug relay and I had to get going, so I parked it and told him I'd come back later and swap the relay out. When I did we tried to fire the truck up, and it wouldn't start. It would barely run at all, then sputter and die like it was starved for fuel. It would only restart if I shut the key off; if I just cranked it over again it would only crank- no fire. I fiddled with it and finally got it running again, he drove the truck into town and back (about a 10 mile trip) and when he got home he had it idling in the driveway and it sputtered and died again. Fuel filter is new, fuel pressure is good, no codes, new CPS, everything else checks out. The oil was about a quart low, not low enough from my experience to cause it to shut off and even so, that's normally a quick shut off like you turn the key off; not a sputter out and die situation.
I'm at a loss but I promised to get this rig back on the road. Any help would be appreciated.

[jjdude]

Did you replace the cps with a OEM or aftermarket? I read about a lot of problems with them. My autozone unit lasted a month. JUNK!

[superduty4x4]

I didn't replace it, it was replaced prior to me touching the truck. The symptoms are not classical CPS symptoms, it seems to be fuel or oil related.

[ol_Blue97]

try checking fuel and oil pressures right off the rail and shrader valve to see real time what you have.

[backwoodsboy]

A friend of mine had a similar problem with his '95. Turns out his IDM was on it's way out. I'm not sure why a trouble code wasn't stored, or why swapping IPR's allowed the engine to run normally for a while (I believe it was a day or two in his case), but I saw it with my own eyes so I'll believe it.
Not sure if you've checked the 42-pin connection to the PCM, but I've heard of chaffed wires/bent pins causing similar issues.
Noticed you're over on NWFD as well. If the truck is close enough to B'ham and you're looking for an extra set of hands give me a shout.

[superduty4x4]

Originally Posted by ol_Blue97

try checking fuel and oil pressures right off the rail and shrader valve to see real time what you have.

Fuel psi was 50ish, I can't recall what the HPO pressure was but it was fine. I didn't have my laptop the second day to check it again.

Originally Posted by backwoodsboy

A friend of mine had a similar problem with his '95. Turns out his IDM was on it's way out. I'm not sure why a trouble code wasn't stored, or why swapping IPR's allowed the engine to run normally for a while (I believe it was a day or two in his case), but I saw it with my own eyes so I'll believe it.
Not sure if you've checked the 42-pin connection to the PCM, but I've heard of chaffed wires/bent pins causing similar issues.
Noticed you're over on NWFD as well. If the truck is close enough to B'ham and you're looking for an extra set of hands give me a shout.

IDM is what I was leaning toward as well. I would doubt it would be a PCM issue, this isn't a modded truck.
Yeah I'm on NWFD as well, but I'm on the dry side of the state over near Spokane.

[superduty4x4]

Got it figured out... frickin burned UVCH of all things.

[backwoodsboy]

Glad you got it resolved