Stalling problem on Suburban w/checklist

[dracor85]

The Diagnostic Checklist:
Please fill out to best of your knowledge.
1997 Chevrolet Suburban K2500


1. Describe the problem you are having in detail: The sub has been having stalling problems for the last two weeks. Mostly it has happened cold when leaving work, it would start fine you would back up and it would start to miss and stall. Restart runs rough (like air in lines) for 30-60seconds and then smooths out and runs fine. Took it to my house sat for 4 days pulled it onto drive way (today) Pulled it out of the garage ran for 5 min ran fine. parked and swaped pmd's with "NEW" D-Tech unit ran fine for 20min idleing then stalled (engine was up to temp). Restart runs rough and dies. Crank, Crank, Crank, Sputer, Crank, Sputter, Crank, starts runs rough smooths out runs for 5 min stalls. Crank, Crank, Crank, Sputter, Crank, Sputter, Crank. let sit 5 min. crank, sputter, crank, start let run for 1 min then i went through a few cycles of reving the engine holding it at 1500rpm 2000rpm 2500rpm idle stall. re start crank sputter crank sputter let sit. while sitting i trouble shot the lift pump jumpered it to blead the filter housing and water drain.. re start runs swaped trucks around in the drive, let idle for 45min went out reved it up to 2000rpm died with revs going then wouldnt restart just crank, crank,crank,crank. so thats where im at. Im seeing if a buddy will bring his scanner down to find out the code any tips for scanning with a Snap-On "modias"? -I think thats what its called. . Year of truck/engine.1997 (12-96 build date)
3. Odometer reading (indicate miles or kilometers). 175,738mi
4. Indicate the model number on the Injection pump (starts DS4 or DB2......). guessing a DS4 being a 97'
5. Indicate if you know if it’s a 1500, 2500, 2500HD, 3500, 3500HD.2500
6. Do you have an EGR on the engine? (An F or an S engine code 8th VIN digit) F vin non-EGR
7. Air Filter condition (visual check). ok
8. Fuel filter condition (freshly changed, mileage since changed). appx 10k mi since change
9. Location of PMD/FSD? (ex. on pump/remote over intake, behind bumper). located on the intake with a ssdiesel kit but a "NEW" D-Tech pmd put on Today with no change
9a. If remote mounted, describe wiring harness (homemade or purchased from which vendor). stock harness
9b. Indicate the location and condition of the FSD/IP grounding wire. grounded to the intake
10. Outside Temperature (C or F). _68_ °

11. Service Engine Light while running?- on/off/intermittent was off but came on today when stalling
11a. Service Engine light does glow during start/cranking/bulb check: Yes/No yes
12.Have you scanned for engine codes? Yes/No Not yet but I will tonight
12a. List exact results on engine codes.

13. Condition of Battery terminals (removed, cleaned and tightened). Good
14. Known condition and age of Batteries. 2mo old
14a. Are batteries a matched set of same age? yes
15. Condition of Major Grounds (removed, cleaned and tightened) Cleaned and redone a few years ago
16. Does engine crank, or "turn over"? yes
16a. Does engine start and run? some times
17. If engine does not start- Crack injector line: do you have fuel? Yes/No
18. Does your Wait To Start light come on? yes
18a.Number of seconds WTS light is lit. cold appx 15-20sec/ warm appx 5-10 sec
19. Engine Cranking speed (if you have an accurate tachometer). normal speed compared to my 95 truck
20. Are you experiencing Stalling? yes
20a. Describe the event (upon startup only, down the road, hit a bump, etc...) Stalling occurs with no consistancy just sitting in flat level driveway no diffrence on road
20b. Do you notice loss of dash or instruments? no
21. Check turbo inlet and air filter for obstructions. ok
22. In a no-hot start, pour a bottle of room-temp water on the injection pump. Does it start now? no diffrence
23. Lift pump test - Describe results. lift pump is on the weak side but still ok. the Sub wolnt stall with either of the bleaders wide open
24. Upon cold start, does the radiator hose get hard quickly? Yes/No no
25. Upon cold start, do you have excessive white smoke? Yes/No no
26. Do you have excessive cranking time before the engine starts? Yes/No no
27. Have you used the block heater? Does it affect engine starting? (only try for starting problems). no
28. Are all glow plugs in proper working order? yes
29. During hard acceleration, do you have excessive black smoke? Yes/No there is more smoke from the sub verses the truck but not excessive
30. Do you have any unusual exhaust smoke issues? no
31. Turbo check out - Pass/Fail pass
32. Indicate fuel that you are using: Bio-Diesel, #2 Diesel, SVO/WVO, other #2 Diesel
32a. If running Veggie Oil fuel setup, indicate details of your conversion (homemade or packaged system). N/A
33. Are you using any fuel additives? If so, please list. no
34. Upon unscrewing fuel cap, do you have a large vacuum formed in the tank? Yes/No no
35. Do you have any service history available that might pertain to the problem you are having? no
36. Please indicate any modifications to the vehicle that might help us diagnose better. Truck has after market airfilter and homebuilt Turbomaster otherwise it is stock


Thanks in advance guys,
Justin

 

[Brooklyn Tow]

Check list says 10k on the fuel filter......Have to start there, also Weak lift pump you decribed, did you put a gauge on it? what was the PSI?

Just that combo alone would result in stalling......Need to put some clear line to check if your sucking air.

If nothing else, it's a good place to start ruling things out.....easy stuff first, as we have heard so many times.

2 Cents


Luck,

 

[NVW]

Check list says 10k on the fuel filter......Have to start there, also Weak lift pump you decribed, did you put a gauge on it? what was the PSI?

Just that combo alone would result in stalling......Need to put some clear line to check if your sucking air.

If nothing else, it's a good place to start ruling things out.....easy stuff first, as we have heard so many times.

2 Cents


Luck,

x2, the grounds are due for a good cleaning as well.

Leo

 

[Dave01]

Definitely first thing to do is change the fuel filter, eliminate the easiest thing first.

I'd get a fuel pressure gauge, attach it at the T valve, and tape it to the windshield so you can watch. What is the pressure when you start up, and what happens when you get to the point that it stalls? I might have said PMD but you eliminated that with the new one, so I'm thinking its fuel delivery. You said no vacuum at tank, and no stall when T valve is open. I'd wonder about the sock in the tank then, that could starve fuel even if you have a good lift pump.

If it was just an air leak I don't think you'd be able to keep re-starting it, you'd have to bleed the injector lines first.

 

[buddy]

So youre saying you get fuel out of the drain and valve when you open them at idle or it just doesnt die? If youre not getting fuel out of them at idle then LP isnt running and you have a relay issue. Or the sock issue as stated above, which a shot of air into the lines could open up.

Also, youd be well served by a quart of TCW3 2-stroke oil in every fillup. #2 ULSD will kill your IP in no time.

Check that the PMD ground is well secured, not loose.

 

[Rodd]

You may also have a clogged sock/strainer located in the fuel tank. That requires dropping the tank so I would rule out everything else first.

 

[Missy Good Wench]

Some times these things will develop an issue with the bypass valve in the tank.

This valve will "SUCK OPEN" and allow fuel to enter if the sock becomes clogged.

If the fuel level gets below this valve the thing will suck air and cause all sort of troubles.

Generally this can be an issue at around 1/4 tank level. Above this is usually fine as the valve is submerged in fuel.

Missy

 

[Turbine Doc]

Some times these things will develop an issue with the bypass valve in the tank.

This valve will "SUCK OPEN" and allow fuel to enter if the sock becomes clogged.

If the fuel level gets below this valve the thing will suck air and cause all sort of troubles.

Generally this can be an issue at around 1/4 tank level. Above this is usually fine as the valve is submerged in fuel.

Missy

????? not sure of what you are referring to here MGW, last time I dropped mine the bypass was in the end of the sock itself and lays in the pickup tray in the bottom of the tank with the sock, is that what you are referring to? If that is stuck open you would have big junk going to the lift pump as well and eats out the check valve in the lift pump so it can't build pressure