Stalling. just replaced FSD and extension, and stop-solenoid. fuel pressure ghoes up as stops.

[Aishling]

I cant tell if the fuel pressure goes up before lights-out or just after. It's all I can find as a symptom.
Dont forget I am in Australia !! No parts stores or anyone familiar with GMC/GM Diesel problem-solving.
Problem: Stopping when accelerating engine.
I have been suffering intermitent stalling for a while. Ute (Australian for little truck) usually starts instantly without issue whilst still rolling.
I ordered new FSD and Extension cable, new Pump pigtail, new Ignition key wiring pigtail, new fuel shut-off solenoid (on IP).
While waiting for shipping to Oz- problems get worse as in more regularly stalling (eventually daily) and wont restart quickly. Longer waits between start attempts are successful. Eventually almost impossible to get going (starts and then dies quickly). I have taken apart all wiring in engine-bay and checked and dialectric-greased joiners.
Parts arrive - I replace the FSD and extension cable (thanks Leroy), and the Fuel shut-off solenoid. I replaced the fuel pressure guage between filter and IP. I did some driving around the farm - all seemed good. In afternoon I hitch-up 5th wheel horse float, load and leave. ute drives 1000Meters and stops. restarts easily. As soon as I accelerate it stops. Harder to start after the second stop. This cycle gets worse. Quicker shut-down and slower to recover to be able to restart.
After thinking about it I checked the return fuel-line flow by pulling-off the hose from IP. Plenty flows out. Ute starts well and I return to farm with a few stops (gets drastically worse along the 100M trip). I used aircompressor and blew out return fuel-line with tank cap off: seems fine. I set off again and got further but still gave up and went home.
A day later I removed FSO solenoid and it seems to work fine. I can start and idle almost indefinitely. 6PSI on fuel pressure guage. If I gently press accelerator and raise revs (1000) the moter will die soon (20 seconds-ish). If I stab the accelerator it will die immediately. Fuel pressure observed to go up to 9PSI at engine dieing.

It's got me f_cked....

Demographics: tell us about your truck and your ambient conditions:

- Year: ____ ____________________________1998
- Truck model and class (ie: c2500) _________K2500 Sierra
- Automatic or Standard _________________700r4
- Mileage: (indicate miles or km) _________ 190k Kilometres
- Replaced parts and mods ________PMD, chip/PCM is now KOJO, AT Turbo, Diamond eye exhaust and new 2.25" crossover.
- Model: VIN 1GTGK29F-4WE547828
- Ambient outside temp: (indicate 23 *C
- What fuel are you using? Best quality diesel
- What fuel additives are you using? Morey's oil diesel additive
- Where are you located? South-West of Western Australia

General maintenance: inspect and evaluate the condition of each. When were they last changed?
- Air filter _________10000Km (K47 style)
- Fuel filter _________ 5000Km (big Donaldson 5Micron with water bowl)
- CDR Valve? _________ Unknown
- Coolant – last flushed/replaced at ___4000Km
- Oil – synthetic/regular, changed at __Mineral 5000Km
- Batteries – state of charge, (matched set) replaced at. Good, unmatched except chemistry, 3 months old.
- Battery cables and grounds (removed, cleaned and tightened): new about 10000km. cleaned
- Glow Plugs - how many miles on them? 5000km What type? Bosch
- Injectors - last changed at Unknown. new ones here to go on.


History: (Describe how the problem first appeared.)
- What were you doing when it happened? ______________ Towing 4000Kg
- How was the truck running fine before this problem appeared? perfectly except intermitent stalling
- Has this problem ever happened before? simple stalling yes- but always restarts easily.
- Describe any related factors that might be part of the problem. just changed FSD
- Have you checked for DTC (Diagnostic Trouble Codes)? Yes P0308

[/FONT] Diagnostics:

1] Starting:
1a] Does the engine start? _________ yes
1b] Does the engine crank over? ________yes
1c] Are your batteries fully charged? _________yes
1d] Have you removed, cleaned, and tightened all battery connections? ________most
1e] Does your Wait to Start light come on for a time? How long? _________5 -10 sec
1f] Does your glow plug light come on? _________ For how long? _________
1g] Do you see smoke from the exhaust while cranking? What color? none (then black belch when starts)
1h] Does the Service Engine Light Glow during Start/bulb check? yep

2] Fuel Issues (if not running):
2a] Can you hear your lift pump working? ____________yes
2b] Do you get a steady flow of fuel from the water drain (T-handle) ? _________ yes
2c] Loosen the inlet line from the IP – is fuel coming out (Lift Pump on)? ___________
2d] Loosen an injector line and crank the engine - does fuel come out? _________
2e] Do you hear a vacuum (hiss) when you remove the fuel cap? ___________slight

3] PMD / IP Issues
3a] Location of PMD (on pump, on intake, remote mounted) ___________remote - bumper
3b] Condition of Extension harness (if used) Vendor or Homemade? _________Vendor new
3c] Condition of grounds / ground wires to IP / PMD. Check Harness. _________checked, extras added.
3d] PMD Make: ___________ Flight systems
3e] PMD Age: _____________new

4] Stalling Issues
4a] Do you experience stalling only when hot? ____________ usually
4b] Does it stall under particular circumstances? at the moment at accel
4c] Does pouring cool water over the IP seem to help with restarting? _________
4d] Is stalling momentary (engine recovers)? _________ used to - not now
4e] Does SES light come on when engine hiccups? _________no
4f] Does cruise control quit working when engine hiccups? ___________
4g] Does re-starting seem to reset engine, restoring cruise and power? _________
4h] Changes to dash lights or instruments during stalling events? ___________no

5] Running Issues
5a] On cold start, does upper rad hose get hard before engine warms up? _______
5b] Any bubbles or oil film in coolant overflow tank? _______
5c] Any white slime on oil surfaces (dipstick, CDR, oil Fill cap)? __________
5d] Excessive white smoke from exhaust on cold start? _________
5e] Excessive black smoke from exhaust under hard acceleration? __________

6] Performance Issues
6a] Do you have gauges (boost, EGT) ? ___________ not working
6b] Maximum boost under load? ____________
6c] Have you added a performance PCM (reflash) or Chip? ______________Kojo
6d] Have you changed exhaust / downpipe / crossover? ________________DEye and cross
6e] Wastegate – mechanical or vacuum (OEM)? ______________ None

7] Temperature-related Issues:
7a] Single or dual thermostats? ____________ Dual
7b] Have you replaced them lately? Manufacturer of replacements? _________10000Km Tridon
7c] Have you pulled and cleaned Radiator and coolers lately? ____________New 2000Km
7d] Have you replaced the fan clutch? Manufacturer of replacement? ________
7e] (winter) Have you tested your antifreeze? Good to what temp? __________
7f] (winter) Are you using a winter grille cover? ___________

List and describe any other factors which are not addressed in this checklist.

 

[ak diesel driver]

Sure sounds fuel related. Run a couple of gallons of fuel out the water drain to check for volume/flow. Is your fuel pressure gauge in the cab? Maybe try leaving the fuel tank cap loose.

 

[Will L.]

Please describe the fuel pressure more. Fuel pressure is X before starting, fuel pressure is X when accelerating, feel pressure is X when engine dies.

Replace the 1/4 inch diameter return hose coming out of the IP with clear hose to check for air intrusion.

You said it dies faster under accelerating harder, what about the truck not moving and revving up the engine while it is parked. Does this cause the engine to die in same amount of time?

I agree with AK, i'm thinking fuel. The only electrical I could think of is the fuse you guys have that sometimes gives fits. That could cut power to the pmd. The ignition switch dilemma was solved by the time his truck was built, right?

 

[jrsavoie]

I always run about 1/2 gallon or more of fuel out the T drain as part of my diagnostic process. I use a gallon pickle jar to catch the fuel. Look for crud while you are running the fuel out and look for water bubbles on the bottom of the jar. I usually let it sit for 20 minutes or so. Sometimes it takes a while for the balls to form.

A fuel filter is only as good as your last tank of fuel. I'd check it.

2c] Loosen the inlet line from the IP – is fuel coming out (Lift Pump on)?

Since your fuel pressure goes up, it would seem you have plenty of fuel to the IP.

Otherwise I would suggest dropping your fuel tank and checking for crud there.

Is there a last ditch screen at the injection pump inlet?

 

[jrsavoie]

Please describe the fuel pressure more. Fuel pressure is X before starting, fuel pressure is X when accelerating, feel pressure is X when engine dies.

Replace the 1/4 inch diameter return hose coming out of the IP with clear hose to check for air intrusion.

You said it dies faster under accelerating harder, what about the truck not moving and revving up the engine while it is parked. Does this cause the engine to die in same amount of time?

I agree with AK, i'm thinking fuel. The only electrical I could think of is the fuse you guys have that sometimes gives fits. That could cut power to the pmd. The ignition switch dilemma was solved by the time his truck was built, right?

We had to change out the ignition switch on our 1998 K2500 Suburban. So I do not know that the ignition switch issue was ever totally resolved.

 

[WarWagon]

Clean the electrical Grounds.

 

[jrsavoie]

And add the extra grounds. Could also be your engine harness. I've been replacing my engine harnesses as I work on vehicles. Mine are all getting old and brittle - like me.

 

[Aishling]

Right. Thanks so far. Grounds were cleaned recently but i will recheck.
Last ditch in pump still, will check.
I added extra grounds - battery(s) to body and engine both sides. Extras to intake manifold and intake upper.
i ran fuel over my hand yesterday which looked great. will check in jar.
My fuel pressur guage is underhood, so only observed parked with someone else moving accel pedal.
At key-on fuel pressure goes to 6psi. (flickers 5.5-6.5 as pump cycles) fuel pressure settles as motor idles to 6. When engine is 'revved' it almost immediately dies -pressure goes to 9. if revs are raised carefully then fuel pressure remains about 6-7 then goes to 9 as engine dies.
thanks again. I'll check back later. Peter

 

[jrsavoie]

You also need to make sure of the frame ground and add the ground from the heater blower to the dash mount bolt a few inches away.

Did you add a ground to the stud that all the grounds go to on the back of the engine? I've seen thatq stud lose ground more than once. With a ground wire running to the stud, it will still be grounded.

 

[Aishling]

Maybe solved.. Pulled the shutoff solenoid from ip. Fuel flows out nicely so pumping fuel in not the problem. short version of an hour from there was that i dimmly remembered something about the FSO being redundant on my model. So, i pulled it and cut off plunger and screwed back. IT LIVES.
That bloody FSO was new put in on friday.
Side note: i tried the old FSD briefly (still mounted in grill) - it didnt fly, so replacing fsd must have been the longer-term problem.
Thanks for your thoughts - i now know a new glitch in 6.5 ownership.
Does anyone suggest i replace the FSO again?

 

[jrsavoie]

Are you using AC Delco or GM parts for the FSO? For many sending units, thermostats and some other parts, OEM is the best way to go

 

[Aishling]

You also need to make sure of the frame ground and add the ground from the heater blower to the dash mount bolt a few inches away.

Did you add a ground to the stud that all the grounds go to on the back of the engine? I've seen thatq stud lose ground more than once. With a ground wire running to the stud, it will still be grounded.

Thanks JR. I have an extra (big) ground wire from passenger battery to middle stud and to Firewall. Extras from driver's (US) side battery to other mid stud and to radiator support panel. oh and another directly to the starter motor. bloody grounds....

 

[ak diesel driver]

I'm kinda anal but I'd put a FSO back on. My thinking is it would still shut down the engine with a runaway condition.

 

[Aishling]

Attached image my whole engine ba. Had to reduce quality but some of you may be interested by right hand drive.

 

[Aishling]

This shows the cut-off new solenoid next to original i replaced because i was suspicious of it... Oh well, nack to ebay/vendors. Leroy? You got em?

 

[NVW]

The fuse for the FSO could be your problem, mine gives me grief with poor contact with the fuse spades.

 

[ak diesel driver]

I'd try the old one again

 

[WarWagon]

I'm kinda anal but I'd put a FSO back on. My thinking is it would still shut down the engine with a runaway condition.

Only at key off. The ECM contains no logic to use the FSO. The ECM would try and reduce or shut off fuel with the PMD that controls the IP spill valve in the event that desired RPM is way over. But under no conditions other than key off does it close the FSO.

Blow a turbo seal or suck oil with the CDR and the only way your are shutting it off is killing the air.