0.Describe in detail the problem you are having. Please be as descriptive as possible.
Truck starts up just fine, sometime will die within seconds, most of the time will run fine for awhile, as soon as I get up past 2000 rpm’s it will stumble a bit, so I changed the oil it was due, fuel filter, and even the lift pump along the frame rail. Was running good for a couple of days, then the worse started to happen, it died repeatedly while driving home from work. Had to stop traffic at 5 p.m. pissed off a lot of people, put it in park and turn the key and fired right up, proceeded to head home, and started to stall/sputter/shake like a paint mixer, so stepped on the gas to keep from stalling, to the floor could only do 25 mph, at like 2000 rpm’s, got home and assumed it was the OPS, I changed it 3 years ago when I got the truck it was shot. Anyhoo, went to test drive it and it was idling fine at first went to put in drive got 15 feet and it stalled out, so had to coast it back to driveway and start figuring out what it could be. And I am completely lost. I am mechanically inclined but am lost with this truck as to what it could be. It is getting fuel, I know that for sure. I had to borrow the wife’s wheels to get to work and she is pissed because she is stuck with a truck that can double as a vibrator. And to top it all off I can’t get the codes from the computer in diagnostic mode.

1. Does the engine crank, or 'turn over'? YES
1a. Does the engine start and run? YES
1a1. If the engine does not start - Crack injector line: do you have fuel? Yes/No YES
1b. Do you have a Wait To Start Light & the amount of time (seconds) lit. YES
1c. Ambient Condition (temperature outside indicate F or C) _____ ° 94
1d. Engine Cranking speed (if you have an accurate tachometer). Not sure
1e. Are you experiencing stalling? YES
1f. If Stalling, describe (upon startup only, down the road, hit a bump etc) SOMETIMES STARTUP USUALLY DRIVING IN GEAR.
1g. If Stalling, do you notice loss of dash or instruments? NO
-note if experiencing stalling,you must indicate PMD location in #24.

1h. Check turbo inlet and air filter for obstructions. Cone filters have lost disk and stopped air to turbo.
1.1 Lift pump test - describe results JUST REPLACED
2. Service Engine Light while running?- on/off/intermittent OFF
2a. Service Engine light does glow during start/cranking/bulb check: Yes/No YES
3. Model year 1994
3a. Odometer reading (indicate if in miles or km) 137000
3b. Miles on major engine components if been replaced (example Injection pump) NOT SURE
3c. Indicate the model number on the Injection pump (starts DS4 or DB2......)
4. Have you scanned for engine codes? (varies by pre/post 96) yes/no HAVE TRIED TO BUT NO LUCK
5. List exact results on engine codes: NONE
6. Air Filter condition (visual check) BRAND NEW
7. Fuel filter condition (freshly changed/condition unknown/mileage since changed) CHANGED 1 WEEK AGO 100 MILES
8. Condition of Battery terminal connections (removed, cleaned and tightened) CLEAN AND TIGHT
8a. Known condition and age of the batteries. 2.5 YEARS
8b. Are batteries of differing age or are they a matched set? MATCHED SET
8c. Condition of Major Grounds. (same drill as batt - removed, cleaned, retightened)
9. Upon cold start, does the radiator hose get hard quickly? Yes/no NOT SURE
10. Upon cold start, do you have excessive white smoke? Yes/no NO
11. Do you have excessive cranking time before the engine starts? NO
12. Have you used the block heater, and does this effect engine starting?(only try for starting problems) I HAVE ONE BUT IT IS NOT USED
13. During hard acceleration, do you have excessive black smoke? Yes/no SOMETIMES
14. Do you have any unusual exhaust smoke issues? NO
15. Turbo check out - pass/fail NOT SURE ON THIS ONE
16. Do you have an EGR on the engine? (An F or an S engine code 8th VIN digit) AN S CODE
17. Indicate if you know if it’s a 1500, 2500, 2500HD, 3500, 3500HD. 1500
18. Indicate fuel that you are using: Bio-diesel, #2 Diesel, #1Diesel, SVO/WVO, other #2
18a. If running a VO (Veggie Oil fuel) setup, indicate details of your conversion (homemade, or packaged system)
19. Are you using any fuel additives? If so, please list. NO BUT SHOULD I?
20. Please indicate geographic region you are in: (example: Texas or Canada) OLE MISS.
21. Do you have any service history available that might pertain to the problem you are having? NOPE
22. Please indicate any modifications to the vehicle that might help us diagnose better. 4” EXHAUST,
23. Upon unscrewing the fuel cap, do you have a large vacuum formed in the tank? yes/no NO
24. Location of PMD/FSD? On the pump/remoted over intake/remoted out of engine bay (please specify placement specifically) UNDER FRONT OF BUMBER
24a. If remote mounted, describe wiring harness (homemade or purchased from a vendor?) VENDOR, SAME OS FSD
24b. Indicate the location and condition of the FSD/IP grounding wire. ??
25. Are ALL glow plugs in proper working order as per this thread AS FAR AS I CAN TELL

Sounds like fuel to me, how was the filter?
Did this happen after a fuel stop?
Makes me think of the tank sock.

yep just added like 10 gallons friday to get me through the week till payday, i was thinking it could be that. I started it up today and it idled fine till it was warmed up then it started to stumble a little then quite a bit till it stalled. was thinking of checking out the sock, but have never done it before. so i am guessing that could be it too. oh and the filter was brown nasty before so i changed it out last week.

Your problem sounds very similar to mine... I haven't worked on my truck much yet cause I've been.... lazy lol. Plus with fuel prices I'd probably just drive my car for now anyways but I would love to drive my truck cause i miss it :(. If you find out what your problem was let me know :), I might try and work on it this weekend but probably won't be until next weekend.

Did you check for water in the fuel, if no water try removing the fuel filler cap and drive around to see if drawing a vacuum on the tank is causing a problem.

I just had this happen to me my truck would run fine and soon as it warmed up it would stumble and stall. Mine turned out to be the pmd. It doesnt throw any error codes I remote mounted mine and the truck runs great. My guess is when the PMD starts to go bad it gets worse when the engine heats up. They are driven by 2 transistors and heat makes transistors do funny things. If your pmd is in the factory location more than likly thats your demon. Another symtom is that your cruise will kick off.

Looking at the checklist, the PMD is already at the bumper. However, it is still not immune from breaking down.

I know you have a new LP and OPS, but have you checked the fuel pressure?

It is also an S engine, you may want to check the vacuum system.

haven't thought of that. i am gonna have to figure out how to check it out

could i have gotten a bad ops sensor? and could i test it out with it disconnected at operating temp?

went out and got another OPS switch it was a niehoff one and it seems to have fixed the stalling issue. and replaced the bulb in the dash for the check engine light and finally got some codes off of it after a test drive. the codes I got were 32...33...81. now i am not sure but the 32 and 33 have to do with the EGR on top of the intake right? and does it mean i will have to replace it? and the code 81 means Transmission 2-3 Shift Solenoid Circuit. now that one confused me.

Make note of your DTC(s), clear memory. Drive it for a day or two or three and see if the condition returns. If so, pull DTC(s) again and list them if any. I'll withhold my thought till we hear back from ya.

fuel shutoff solenoid? ignition switch? Both can cause occasional stalling problems