One problem after another

[RCpullerdude]

Problem started back in January. Was driving along, made a turn, then once accelerating again, had a small loss of power and slight black smoke. Progressivly got worse and started making noises. New fuel filter, tried new fuel, new turbo, plenty of vacuum at wastegate. At time of last run, it couldn't do 20 MPH up a very slight hill. Parents decided we'd change injection pump. Did so (used injection pump off eBay real cheap, probably bad), and now won't run period with two different injection pumps. Gets fuel all the way to the pump, but none out injection lines.

- Year: __1994____
- Truck model and class (ie: c2500) ____K1500_____
- Automatic or Standard _____4L80-E_____
- Mileage: (indicate miles or km) ____192K Miles_____
- Replaced parts and mods (IP, PMD, chip/PCM, TM, injectors etc) ___IP, intake, Heath PMD, 3" downpipe and cat to 4" exhaust (not plugged)________
- Model: ‘S’ or ‘F’ engine, NA or Turbo, EGR? ______"S" L56 EGR, Turbo________
- Ambient outside temp: (indicate *C or *F) _____Between 40 and 80 F_____
- What fuel are you using? (#1 Diesel, #2 Diesel, Bio, VO, WVO, etc) ___#2 Winter blend______
- What fuel additives are you using? ___Power Service White bottle________
- Where are you located? ____NW PA_________

- Air filter _____Freshly cleaned____
- Fuel filter __Brand new_______
- CDR Valve? ____Tests fine_____
- Coolant – last flushed/replaced at _____Unknown________
- Oil – synthetic/regular, changed at ____Regular 1.5-2K miles ago_______
- Batteries – state of charge, (matched set) replaced at _____Brand new matched________
- Battery cables and grounds (removed, cleaned and tightened): _____All clean and tight_________
- Glow Plugs - how many miles on them? ____Probably 10-15K_____ What type? ______SSD Instant Heats (probably bad, but started fiarly well in much cooler temps than this)_______
- Injectors - last changed at _______Probably 180K or so________

- What were you doing when it happened? ______No start, just replaced IP Smoke, turned a corner________
- How was the truck running fine before this problem appeared? _____No start, it was smoking and had no power Smoke, perfectly normal________
- Has this problem ever happened before? ________Niether has_______________
- Describe any related factors that might be part of the problem. ______None________
- Have you checked for DTC (Diagnostic Trouble Codes)? (Y.N) __Yes__ And? ___None, at all_____

1a] Does the engine start? ____No_____
1b] Does the engine crank over? ___Yes_____
1c] Are your batteries fully charged? ___Yes______
1d] Have you removed, cleaned, and tightened all battery connections? ___Yes_____
1e] Does your Wait to Start light come on for a time? How long? ___N/A______
1f] Does your glow plug light come on? _____Yes____ For how long? ___5-15 seconds, depending on conditions______
1g] Do you see smoke from the exhaust while cranking? What color? ___None_____

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)? ____Yes_______
2d] Loosen an injector line and crank the engine - does fuel come out? ___No______
2e] Do you hear a vacuum (hiss) when you remove the fuel cap? _____No______


3a] Location of PMD (on pump, on intake, remote mounted) ____Heath Remote mount_______
3b] Condition of Extension harness (if used) Vendor or Homemade? ____Heath, good condition_____
3c] Condition of grounds / ground wires to IP / PMD. Check Harness. ___All good.______
3d] PMD Make: ____Stanadyne_______
3e] PMD Age: _____Little over 1.5 years________

When we put the original pump back on, it started, ran real rough, then stalled. It would then occasionally start, run real nice, then stall within 2 minutes or so. Before long it wasn't starting at all. No rhyme or reason for start. Tried two different PMD's that where known good, still no go. Put other pump on, still no go. Please help. I'm literally at my wits end with this thing.

 

[RCpullerdude]

I forgot to mention that the shut off solenoid is working properly.

 

[DieselSlug]

Well, sounds to me as if you have two bad pumps.... If yor gettin fuel to it, but not out of it. Is the ip getting power n such? Bad ground on ip? Yeah, about that ebay pump, sounds like an edam thing, been there done that, never do it again kinda thing.

 

[RCpullerdude]

Well, sounds to me as if you have two bad pumps.... If yor gettin fuel to it, but not out of it. Is the ip getting power n such? Bad ground on ip? Yeah, about that ebay pump, sounds like an edam thing, been there done that, never do it again kinda thing.

I have a Helm manual for it, and according to that, it's the pump. It just doesn't make sense though. How the one pump can go from running to not running just by taking it off and putting it back on.

 

[bison]

Plug good PMD in at the pump,to see if its the ext cable.
You said the prob started by turning a corner,coincidence ,or indicating something shifted,that may have put strain on the ext cable or a engine ground wire,or the connectors behind the fuel filter.
did you do TDC offset after replacing the pumps.

 

[RCpullerdude]

Hasn't run long enough to get up to temp to do TDCO. The only thing that started after making a turn was the smoke. The no start didn't start until three months later.

 

[bison]

If the timing is within the parameters and the IP and PMD is good it should start. did you check under hood fuses?
Maybe now you need to get these pumps tested,IMO the oportunity to trouble shoot before replacing the IP is largely gone.
might have to wait for Buddy to pipe in ,he seems to know the voltages and where to check them in that IP circuit, i could,nt begin to tell ye

 

[RCpullerdude]

There's only one underhood fuse I know of off the top of my head, and it's fine. I went through my Helm factory manual, and it had me test all the voltages and such, and all tested fine. The manual indicated an injection pump.

 

[buddy]

In 94, the fuse center is under the steering column.

The only fuse under the hood is for LP. With truck off put it in gear and turn IGN to START and does the LP run? pump fuel out the drain?

Is the SES light working with engine OFF IGN ON? Do you get at least a code 12 out of it?

The original loss of power and smoke sounds like a vac line cracked. Did you notice lower boost after that?

Bison is correct, first thing eliminate extension cable as problem.

Does it work any differently if you unplug the OS and try running? Or unplug Crank sensor and try it? One or the other has to work for PCM to have any timing reference and try to start the truck.

How are you timing it? Crank at 12, Cam at 12, IP at 6? The crank turns twice for each Cam turn, so make sure youre not 180* out of time.

 

[RCpullerdude]

The LP works fine. SES is working fine. I think the loss of power and smoke is a boost problem, but it's not in the vacuum system or the turbo. One of the two good PMD's was used without an extension cable, still no fix. OS was part of the manual troubleshooting, still a no go. It is all timed properly.

 

[bison]

2 IP not working ??? hard to believe,i would start continuity checking the engine harnass and grounds in the engine bay,including the connectors and firewall harnass flexpoints for broken wires inside the insulation.

 

[RCpullerdude]

2 IP not working ??? hard to believe,i would start continuity checking the engine harnass and grounds in the engine bay,including the connectors and firewall harnass flexpoints for broken wires inside the insulation.

That's what I thought, but one IP is questionable, and the other was throwing a 36 occasionally.

 

[NVW]

I think this would be included in bison's list but don't forget the short harness that plugs into the PMD coming off the pump.

Leo

 

[buddy]

Did you try unplugging OS or CPS and with what results? Have to note any differences in cranking or have you tried that with the original that was starting and dying? Kind of have to limit the variables or start detailing which IP with which results.

Do you get the DTC12?

Do you have a digital multimeter?

 

[RCpullerdude]

Neither did any different with OS unplugged. Didn't unplug CPS. I used my GMTDScan Tech to check for codes. I have a multimeter, and used it to check the various circuits at the PMD connector as outlined in the GM manual for diagnosing a no start.

 

[bison]

Maybe you should take both IP's to a diesel shop,if there's one in the area ,and have them tested to rule them either in or out.
right now it seems you are groping in the dark, and flipping coins aint gonna help much.

 

[DieselSlug]

if i had my new engine in i would have an extra that i know is good, if i twould work on your truck.....

 

[RCpullerdude]

Maybe you should take both IP's to a diesel shop,if there's one in the area ,and have them tested to rule them either in or out.
right now it seems you are groping in the dark, and flipping coins aint gonna help much.

Yup. Got a really, really good deal on a known good one though.

if i had my new engine in i would have an extra that i know is good, if i twould work on your truck.....

Thanks for the offer, but as I told Bison, I have one on the way.

 

[RCpullerdude]

Little update:

I got a known good pump and put it on. I do believe it will run now. I just had it fired up here not too long ago. Now, I have found a new issue. I hooked my GMTDScan Tech up to read the codes, and though there are none, it says the shift lever is in second. Problem is, the shift lever is without question, in park. Any suggestions? Maybe Friday or this weekend I'll go out, get it up to temp, and set timing/TDCO (thanks for the sticky, gmctd).

 

[Matt Bachand]

Stll starts up?

What does it do when you shift around gears?