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More questions than answers part 1 million

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Injection pump timing

’99 Ram manual transmission - rebuild or replace

Why won’t this truck run 1999 3500 sport . Remanufactured pump from thoroughbred diesel no fuel at the number 1 cylinder and poor fuel delivery from the first 3 lines. Cylinder 1 2 3 . The cylinders 4 5 6 are spraying fuel . New fass ddrp pump 16 psi of fuel to the pump turn the key the pump runs a second then shuts off like it should . I have sent 12 volts and ground direct to the injection pump it still won’t run . Throughbred is sending me a breakout box What can it do that I haven’t done already ? I also checked the blue wire no power there just to be doubly sure I cut like I read to try on blue chips diagnostic pages . Not sure what else to do at this point . Injectors have been tested the original set out of the engine had one that wasn’t great I swapped them with another set I had tested and they were good . Power and fuel it should at least run according to what they tell me . Also removed the pump sent it back to thoroughbreds shop they say it’s perfect they say they could send me another but I don’t see any point in that
 
I assume you are reporting 16 psi at the inlet port of the HPP and post filtration? Seems strange that you have good fuel delivery on every other pressure pulse so I was curious if there may be a flow issue and starving the pump between pulses....
( 1 nothing, 5 good, 3 weak, 6 good, 2 week, 4 good. ) o_O
 
Is there anyway that
I assume you are reporting 16 psi at the inlet port of the HPP and post filtration? Seems strange that you have good fuel delivery on every other pressure pulse so I was curious if there may be a flow issue and starving the pump between pulses....
( 1 nothing, 5 good, 3 weak, 6 good, 2 week, 4 good. ) o_O

Well, I wondered that, but there’s gallons of fuel at the inlet to the injection pump. I replaced the tank module because it had that stupid pump on it And that quit, and I think it was restricting fuel pretty much everything’s new or been tested good on the fuel system, except the line between the tank and the injection pump and yes 16 psi right on the button So I really don’t know I think it might be in the ECM I bought a used harness off another truck I’m gonna swap
 
Is there anyway that


Well, I wondered that, but there’s gallons of fuel at the inlet to the injection pump. I replaced the tank module because it had that stupid pump on it And that quit, and I think it was restricting fuel pretty much everything’s new or been tested good on the fuel system, except the line between the tank and the injection pump and yes 16 psi right on the button So I really don’t know I think it might be in the ECM I bought a used harness off another truck I’m gonna swap

Didn't we read that the ECM isn't involved during startup aside from providing power to the VP44, that the whole startup is solely controlled from the VP44 itself that hands over control of fueling after the Engine reaches idle speed.
 
Ok to answer everyone in a blanket reply yes you should be able supply 12 volts and ground and fuel to the pump and in theory it should run but it will not run I did it get to run one time on ether albeit not well . The only thing I can think is something is back feeding a signal of power or ground to a pin that it shouldn’t be I just cut the old end of the harness off going to replace that .
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3 cyl idle uses 4,5,6 so 1,2,3 are shutdown.

What’s your IAT sensor showing the ECM for temp? Do you have a IAT fooler on the truck?
 
I could be wrong here, but I think this issue with his truck has been going on for 9 months or so. There are two other threads on this issue by @SAndreasen that people who are trying to help may not aware of. And, if I am understanding correctly, the symptoms of the replacement VP44 pumps (plural) are the same symptoms of the pump that "failed" originally.

I would start my troubleshooting from scratch. Go back to the basics. My first step would be to disconnect the grid heaters and then open up the air intake at the left side of the engine and give the engine a shot of ether. If the engine fires and runs on all six cylinders briefly, but smoothly, then you know the engine is mechanically sound. If it doesn't, then you know you have been barking up the wrong tree.

If it does run, then my next step would be to make sure that the VP44 pump drive gear is still mechanically timed with the valve train.

If everything mentioned above checks out, then I would write down a condensed history to include what originally caused you to investigate the problem. Then using dates and dialog, list the events of your diagnosis in a chronological order.

- John
 
Yes this project is long and don’t get to work on it much it’s not super high on the priority list . I’ve listed what I’ve done the only thing that makes sense is that the ecm has somehow got itself stuck in warm up mode because there just isn’t fuel to 123 cylinders I have an ecm off a running truck that u am going to swap and reinstall the pump and see what happens and report back
 
3 cyl idle uses 4,5,6 so 1,2,3 are shutdown.

What’s your IAT sensor showing the ECM for temp? Do you have a IAT fooler on the truck?

what do I need to acces what the ecm is seeing ? Your warm up theory makes more sense than anything . Everything on the entire supply side of the fuel system has been checked and checked again fifty times now the high pressure side has been tested and checked the new injection pump has been retested the high pressure lines have been cleaned the injectors have been tested . To quote Tony beats it ran the day I shut it off . I don’t see how anything that catastrophic could happen in the 12 hours from when I turned the key to when I went to start it again .
 
it ran the day I shut it off . I don’t see how anything that catastrophic could happen in the 12 hours from when I turned the key to when I went to start it again .

Then the same logic should be applied to "what if the ECM is making it run on three cylinder high idle". If that was the case, then 12 hours later the engine would have started and ran on three cylinder high idle. But, it would have started.

- John
 
Then the same logic should be applied to "what if the ECM is making it run on three cylinder high idle". If that was the case, then 12 hours later the engine would have started and ran on three cylinder high idle. But, it would have started.

- John

imless the ecm has lost its marbles what else can it be ? The pumps are good fuel supply is good . gear slipped on the camshaft and now it’s not in time ? Did get it to run once but not well so I don’t think anything to catastrophic happened sitting over night
 
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