02 3500 4x4 Dually Cummings Ongoing problem for the last few weeks, Something going on with either injectors or fuel pump ? While driving the truck it will be driving no problem, acceleration is good, then at any time the acceleration will just flatten out, I cannot increase speed at all without flooring it and then it will recover and be fine for a little while but will do it again. Last couple of days it has been real hard to start. Seems like there is no fuel getting to it. It is fine in the morning after sitting overnight without running but about 10 minutes into the drive it will start the flattening out thing again. Thought it might be fuel filter, changed that a week or so and no improvement. Checked and drained the water separator so that shouldn't be a problem. Also, there is no check engine light so I can't even get codes to pull. Sort of at a loss as to what direction before I drop several hundreds on the wrong direction.
Thanks for any input or help in advance.

Truck only has 78K on it also.

 

Sounds like the lift pump has gone out. I would get it fixed before you ruin your 1200 dollar injection pump. They don't like being starved for fuel.

 

Lift pump? is this the same as a fuel transfer pump? I have a Haynes book and it doesn't list a lift pump, just a ftp. Thinking the same, located at the left rear of block above the starter.

 

Lift pump and transfer pump are the same thing. It might also be the accelerator pedal position sensor. The truck is fly by wire and the sensor can get dead spots in the windings....

 

you could only pray that it is the lift pump and the apps! i just had the same issues and it turned out being the $1200 injection pump! Not hard at all to change but extremely expensive. try taking the truck to advanced or autozone and see if they can check for codes. even though the light is not on there still can be codes in it. this is what mine had and what helped me to pin point what was the problem, plus i had the chrysler tester that told me what the apps was reading so i could rule that out.

 

Would this fall under Cummings Warranty ?
Truck is a 2002, with only 78,000 miles on it.

 

i am kind of doubting it will be covered under warranty. i just did mine which is an 01 with 66k on it and it wasn't. if you post the vin or pm parts/service with it then im sure he could run it and tell you.

 

If what you are experiencing is "dead pedal" loss of power and no boost on turbo, at any throttle position or speed it's the computor on the vp44 pump. Take a look on Blue Chip diesel webpage, a good explanation of issues with the vp44 pump. I had to replace mine, sounds like same issues you're having, at 66,000 miles, and no, cummins nor chrysler will warrentee it.

 

It could be your MAP sensor? Just a thought.

 

Do you have a fuel pressure gauge? I think EVERY Dodge Ram should have at LEAST that one gauge !! Knowing what your fuel pressure is is extremely important.

With that said, if you haven't replaced your lift pump yet, even if it isn't the problem, do it now. It's not a matter of IF it's going to go, it's a matter of WHEN. Replace it with a FASS and you'll sleep better at night. Should you decide to blow it off until later, you WILL be replacing a $1200.00 VP-44 injection pump. I can promise you that.