the truck sat for about a month, and before that was run only occasionally, but with no problems. the other day i went to start the truck and had the problem. engine turned over for about 10 sec and the stumbled a little and then died. after that the truck would start but would only continue to run if my foot was on the accelerator pedal. (and when i say run, i mean very rough stumble at 1500-2000 rpm, with white smoke). a soon as i take my foot off the accelerator, the truck dies. the glow plugs seem to be operating normally, the lift pump is good to go, and the pmd is fairly new.( i still suspect the pmd, but the symptoms are all of a sudden, and are occurring on a cold start.
So my question is for the pmd experts and gurus; as well as anyone who has had similar problems: Is it the pmd? is it old/bad fuel? is it the injection pump?
Thanks to all...

Being a 94, how is your OPS? it controls the LP when running. Try putting 12V direct source to LP to see if you can keep it running.

Where do you remote your FSD?

Last i checked the lift pump was workin like a champ, but ill check tomorrow.(Snowed like 15" today here in Asheville, so i was a little busy) If the lift pump/OPS had gone kaput, wouldnt the engine at least idle though? this thing barely idles with my foot to the floor on the accl. and "idle" is pushin the term. its ROUGH, like rattle the hood rough. this just worries me a little cause ive never seen anything like this, and ive had the lift pump fail with all the symtoms as well as FSD failure (a few actually) with all the symptoms. The FSD is mounted on a cooler in front of the left battery. Thinkin bout the airbox next if FSD turns out to be my problem.
Thanks for any ideas/advice...

White smoke means u are not getting enough fuel to much air. Check filter and fuel lines make sure you are not getting any air in the fuel. Run a short clear hose off the top of your injector pump to check for air bubbles.

I'd vote for air in the fuel too. Take a look at the fuel lines under the truck. I've seen the lines really bad over the rear end near the left shock tower.

Will do, good call fellas, thanks.

It may just be air in fuel but non working LP can cause air also causing the IP to suck all the fuel from the tank which is a no no. Try to bleed the air, did you change fuel filter or something that causes air in fuel?

Bad OPS will cause the LP to not run after cranking. Try to jump the LP to 12V direct source. See if you can start without stumbling. If you do, OPS is bad and LP is good. If not, LP is bad and OPS is bad. Once all these are corrected and you still could not start, then PMD is bad.

mine did the same thing before and guess what it was.......?????!!!!!!??? some how my turbo sucked in insulation into the turbo tube and was not allowing enough airflow to keep the motor running.... check that out man.. take off the turbo tube(black tube that hooks from the filter box to the turbo) and check it out for and debri.............