Lift pump question

[Mesenbrink]

I did a search but could not find a direct answer. I have a 2004 355/505 2500 4x4. When I turn the key on ,with out starting the engine, my lift pump continiously runs. From everything that i have read it should build pressure and shut off. My truck only has 23,000 miles on it. Any ideas, or how I would go about trouble shooting? It does feel a little weak in the power department and there are no codes or check engine light. Thanks

 

[p-Bar]

Well these engine mounted fuel pumps don't seem to last to long usually they will get about 70k then they fail. Yours sounds unique does it seem to start ok? would be nice to put a fuel pressure gauge on and see whats going on.

 

[BIGNASTY]

Trash It

If it were mine I wouldn't even chance it Just buy a Fass/Airdog/ or better yet build a system. I have an Air dog 100 nothing wrong with it but you can build one and have better filtration for the same or less$$$$ TJMO

 

[BIGNASTY]

More info

Im sorry I had to get info on the guy in my opinion that is the yoda of fuel filtration you need to talk to this guy AD64ID he helped my untill Im sure he's sick of all the questions

 

[rbattelle]

I did a search but could not find a direct answer. I have a 2004 355/505 2500 4x4. When I turn the key on ,with out starting the engine, my lift pump continiously runs.

In 2003 and 2004 the original Cummins software had the LP kick on for 2 seconds when the key is switched to "on".

Later, some time in 2004, Cummins made the decision to change the software so that the LP will run for up to 30 seconds once the key is switched on. If you experiment, you should be able to turn the key on and time the pump and it will shut off after about 30 seconds if the engine isn't started.

This change was incorporated as part of a reflash which changed/fixed other issues. So any trucks that have been back to the dealer since 2004ish will likely have the longer-running LP software. Unflashed trucks (like mine) still have the 2-second version.

This is perfectly normal and is no indication that anything is wrong with your LP. Frankly, I wholeheartedly agree with the decision to go to a 30 second on-time. I do this manually with my truck now.

Remember the ECM doesn't directly measure LP output pressure. Rather, if the LP fails, the engine will set a code indicating low injection fuel pressure because the CP-3 may be starved for fuel. There is no LP pressure sensor on these trucks from the factory.

-Ryan

 

[jelag]

We've got an 04 that had the factory lift pump fail at 80,000 miles and the dealer installed the tank mounted unit... . we also have installed a 10 micron primary and a 2 micron secondary filter on the frame... that truck now has 290K miles... and the tank lift pump is still doing its job... for 250K miles of that's trucks use it was connected to a 20K lb trailer we towed around the pacific northwest... . Down I-5 to San Diego, across to Phoenix and back up I-15 to MT and back to Spokane.....

We changed the fuel filter yearly and the system has worked well, however this truck no changes in HP... . its a stock truck... .

We're happy with the change... .

 

[subodh]

build own system for less $$$ and better filtration? please tell me more i have the lp in my tank and my cp3 is or isent getting fuel its on the edge after my uppgrades

 

[BIGNASTY]

Fuel Sys.

Look at some of the pumps from Air Dog / Fass and you can get the filter heads from Glacier Diesel you can get better filters that beat the ratings of the AD and Fass system. From truck parts stores. He might not mind but again talk to the guy that is in the above post he has help me alot Im sure ive made him a bit gun shy with all my questions.

 

[Mesenbrink]

Sounds like mine just has the updated software. Thanks for all your help everyone.

 

[rbattelle]

Sounds like mine just has the updated software. Thanks for all your help everyone.

With only 23k on this truck that stock pump should be good for awhile longer. They tend to die between 50k and 70k.



Plenty of time for you to consider your options. However, it wouldn't be a bad idea to pick up a spare to carry with you, just in case. Even if you're not handy you would be able to turn over the replacement to a mechanic and he could get you back on the road cheap in just a short while.



Something to ponder, I guess. At your mileage rate it's likely to be many years before that OEM pump craps out.



-Ryan

 

[subodh]

so if i understand right i could go with a fass 150gph without filter and put in some of the aftermarket from the dealer here then. . or is the stock filter enough? have really good fuel up here i scandinavia