• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

6.5 fuel help please

B

bralos

New Member
Messages
22
Reaction score
0
OK first off thanks for any help here.

1994 C3500 6.5. Bought 2 month ago Ran OK. Check engine light would come on after drining 1/8 mile or so but go off after engine shutdown. bought Code reader and looks like Injector 7 is bad but have had to drive it off and on. (only a farm truck) Went to NAPA to buy injector and stalled and had to push back into parking lot but started after a min or 2 and run ok. Got home and parked over for about 2 hours. Went out to move into garage to put in injector and started right up drive 20 feet and died. Has not stated again. Cranking fine, Checked all fuese. Glow light come on and stays on when cranking but will go out after i stop cranking but comes back on after a key off and back on. Tired WD40 in intake (new type) but did not act like it wanted to start at all. Can hear fuel pump kick-in and run for 5 sec after cranking, opened top of fuel filter and getting fuel on crank only. Change out filer as it was due anyways. With key on it does not fill the fuel filter housing but dues when cranking. Broke down as did either, (YES I know, :nono: ) but was not acting like electical. With a shot of either she tried to run so not electical but fuel. When key is on and I un-plug 2 prong flug on injector pump (comes off top of cylander about size of a rool of quarter i hear i click when I put back on. (Think that is the feul shut off????) not sure. So then I took off the fuel line to the #1 injector and get no fuel on crank.

1. Could it be air in injector that need to be bleed? How do I check this?
2. Could it be the injector or fuel shut off? How do I check ?
3. Any other ideas? Thanks a million in advance.....

Jonathan
Down in delaware!
 
Hi Jonathan

Forst, please fill out your signature to let everybody kno0w your truck. Click on the likn in my signature - it will take you to yours.

Second - fill out the Diagnostic Checklist that is linked in my signature... just copy that checklist and paste it into a post, then just click in the blank at the end of each question and type in your response. That will give us valuable information that can help us diagnose your problem (or at least, ask intelligent questions).

Here's a hint... actually, 2 hints. First, put the ether away.

Second, we know if you change enough parts, eventually, you'll fix it, although you will have spent enough to buy a new Duramax. Our goal here is to help you figure out WHICH part to change without changing things that don't need to be changed... and to do that, we need to see/hear/feel your engine, which we do through your careful observations and the checklist.

Hope we can help out... see you when you have some more information for us!

Jim
 
Let me reiterate what Jim has said:

DO NOT SPRAY ANY FLUID INTO YOUR INTAKE TO HELP YOUR TRUCK START.

That is a fast way to blow your motor up.
 
Diagnostic Checklist filled out, best I can at least!

6.5 Engine Diagnostic Troubleshooting Checklist


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

- Year: _1994_
- Truck model and class (ie: c2500) __C3500___
- Automatic or Standard __Auto______
- Mileage: (indicate miles or km) ___189K Miles___
- Replaced parts and mods (IP, PMD, chip/PCM, TM, injectors etc) ___Fuel filter________
- Model: ‘S’ or ‘F’ engine, NA or Turbo, EGR? ___Turbo______
- Ambient outside temp: (indicate *C or *F) ___45F_______
- What fuel are you using? (#1 Diesel, #2 Diesel, Bio, VO, WVO, etc) _#1 Diesel____
- What fuel additives are you using? __Diesel Klean____
- Where are you located? ____Dover Delaware_________

General maintenance: inspect and evaluate the condition of each. When were they last changed?
- Air filter _100 Miles__
- Fuel filter _1 miles_
- CDR Valve? _dont know__
- Coolant – last flushed/replaced at __dont know___
- Oil – synthetic/regular, changed at __dont know_
- Batteries – state of charge, (matched set) replaced at _Fully Charged__
- Battery cables and grounds (removed, cleaned and tightened): ______________
- Glow Plugs - how many miles on them? _No idea__ What type? _____________
- Injectors - last changed at __No idea was geeting blance code on cyl 7___


History: (Describe how the problem first appeared.)
- What were you doing when it happened? __Dring 40___
- How was the truck running fine before this problem appeared? __yes stalled a coule times__
- Has this problem ever happened before? ___NO____
- Describe any related factors that might be part of the problem. ______________
- Have you checked for DTC (Diagnostic Trouble Codes)? (Y.N) _Y_ And? _Only the blance on Cly 7 that I was pullig into garge to fix_


Diagnostics:

1] Starting:
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? _________
1f] Does your glow plug light come on? ___yes__ For how long? __stays on until it starts or done cranking___
1g] Do you see smoke from the exhaust while cranking? What color? _Normal diesel smoke. Well same as ford 6.0 and old tractors when this truck was running, have not checked while cranking__

2] Fuel Issues (if not running):
2a] Can you hear your lift pump working? __Hear a clicking after crank for a few seonds. Sould like priming up___
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)? _Where is this?___
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? ___________

3] PMD / IP Issues
3a] Location of PMD (on pump, on intake, remote mounted) ___________
3b] Condition of Extension harness (if used) Vendor or Homemade? _________
3c] Condition of grounds / ground wires to IP / PMD. Check Harness. _________
3d] PMD Make: __dont know__
3e] PMD Age: ___dont know___

4] Stalling Issues
4a] Do you experience stalling only when hot? ____________
4b] Does it stall under particular circumstances? (ie hit bump, or on accel) ______
4c] Does pouring cool water over the IP seem to help with restarting? _________
4d] Is stalling momentary (engine recovers)? _________
4e] Does SES light come on when engine hiccups? _________
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? ___________

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? __ordered but not here. ___
6b] Maximum boost under load? ____________
6c] Have you added a performance PCM (reflash) or Chip? ____no___
6d] Have you changed exhaust / downpipe / crossover? _____no
6e] Wastegate – mechanical or vacuum? ____no__

7] Temperature-related Issues:
7a] Single or dual thermostats? ____________
7b] Have you replaced them lately? Manufacturer of replacements? _________
7c] Have you pulled and cleaned Radiator and coolers lately? ____________
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? ___________
 
Last edited by a moderator:
Thank for the fast replies, Either is away, well back on tector that requires it anyway. :>
 
Fuel before IP, no fuel at injectors... sounds like PMD.

Jonathan, about your glow plug light... should come on when you first turn on key, then go off by itself after you wait for 10 seconds or so... you shouldn't be trying to start it until after the light goes out. (glow plugs take a lot of juice away from your starter, and until they have cycled, they haven't warmed anything up enough, anyway.
Won't hurt anything, just won't help.

If you turn on your key and wait, does the light come on, then go out by itself after a while? How long?

The fuel inlet line to the IP is located on the top of the IP, right above the PMD. Here's a picture - except that this guy has removed his PMD already. You see the black hose with the hose clamp, right above the red lettering? That's the fuel inlet.

pump_under_inlet.jpg
 
Its about 30F outside, Turned the key on and GlowPlug light was on for about 8 seconds then went out. Cranked engine, turned key back to off for a couple seconds then back on. Glowplug light was only on for a second the 2nd time.

PMD? How do I test it? Or do I just swap it out with a new one? Any other test I should try first?

Thanks
 
Just looked at the picture again. Mine looks just like that one, Nothing above the IP inlet. Are you saying there should be a PMD there? I bought this truck 2 month ago and know nothing about its history except its tranny was rebuild 600 miles ago.
 
Look closer, specifically the black rectangle the red letters are on top of, then look at yours, you should see a similar shaped protrusion about 3/4" think rectangle box. THats the PMD. there will be a harness plugged into it. All you will really be able to make out is the "deck of cards" sized black box.
 
OK the Injection control module. OK now I see what is missing, I was looking below the inlet. She is there. Anyway to test that this is the issue or best to just change out? I am going to NAPA tommorow what are they going to call this the "Injection control module"

Thanks.
 
Getting that one off the IP an another one PROPERLY mounted on the IP is a big job, amigo... you'kk have to pull the intake manifold and likely turn the IP, plus get the right heat-sink mounting compound or thermal transfer pad, plus the right fasteners. Then get it all torqued properly, put everything back together and re-set your timing.

THEN you get to find out if it works...

We don't replace them with a NAPA unit (called a PMD (pump mounted driver, by the way, or FSD - Fuel Solenoid Driver).

We usually order one with a heat sink and extension harness, unplug the ecisting harness and plug the new one into there, mount the new one under the front bumper and just leave the dead one where it is.

Costs a little more, but saves you about 3 hours work. PLUS - they're much more dependable when not mounted to the IP, and easier to change if you ever have to do it again.

Where to get one? Most of us recommend HeathDiesel's PMD Isolator... it is a solid unit, warrantied for 7 years, and backed by the best 6.5 guys around.

But - you can also build one yourself, save some money, and (as long as you do the job properly) still be reliable. Do it wrong, and you WILL get to do it again, and building it yourself means no warranty, so by the time you do it twice, you're about up to what a Heath costs. Your call... we can help you either way.
 
Mine is not mounted to the side of the IP someone moved it horizontal and bolted it to the screw hole shown on the very right side of the picture 3/4 of the way down. Guess this makes it easier to change out and a little cooler. Most have been a old School job way of doing it before the one we are discussing came about. I just hate to go through all that to only find out it was not the problem. I am going to troll the Bone yards to see if I can find a running engine to pull one form to test. If I can verify that this is truly the issue I will then look into changing out to the improved one. Anyone have one laying around they want to sell or rent :smile5:!
 
The entire purpose of it being on the IP is to get COOLED by diesel fuel, if yours is not on the IP, moved next to it, even if it had a heatsync i'm surprised its not compeltely toast now.
 
Can you take a picture so we can see this?

BTW - is it mounted on a silver-coloured, finned alluminum plate that says FSD Heat-Sync on it?
 
Guess this helps to seal the deal on what my issue is. Here is a picture of what i have.

pdm2.JPG
 
uh... we just found your problem, Jonathan...

Nice picture.

Now order yourself a new PMD.

That piece of metal it's bolted to is not going to help the PMD get RID of heat; it will help the PMD absorb engine heat and kill it quicker than ever.

You need a heat sink - aluminum is best, with enough mass to hold heat and enough surface area to dissipate it faster than it absorbs it. It has to be perfectly flat, may or may not have fins to increase surface area, and must have enough mass in the main body to avoid warping and provide for a heat gradient.

You need a new PMD - Stanadyne 35383 or equivalent in DTech. You might need a new calibration resistor.

You need a thermal transfer pad or Arctic Silver heat sink thermal transfer compound.

You need an extension cable - to move your PMD out of the engine compartment and away from the heat of the engine.

Or... you can buy one from Heath, all assembled, 7-yr warranty, plug it in and be going in 10 minutes.

Jim
 
Wish I knew what I know now a few days ago. Never figured that setup was not stock. This is my first Chevy Diesel. Thanks for everyone's help on this one. Glad I found this group. I have posted on a few other Chevy forums on my injector codes and cant get ANYONE to respond. I sure am glad I found you guys!

I am leading towards building my own setup. Have been reading a lot on where some like to put on bumper and other that have even mounted inside the trucks. Think I am going to build a custom setup. I like to fabricate and love a challenge ):h. Will update with pictures as I progress.


Thanks again!
Jonathan
 
You must log in or register to reply here.
Back
Top