Engine/Transmission (1998.5 - 2002) vp44 testing

[dieselsam59]

how do i get the dealer to honestly thouroghly check the vp44? i have a bad lift pump and when cold run at 0 psi. how do i know if they really checked the pump. If there is a code stored will i get a check engine light or something?

 

[csevers]

First off get the lift pump replaced. Does the truck run well? If the truck runs fine and there is no "check engine" light on then that is as good as it gets till you either get a code for the VP or it starts running bad then you will know you have a problem. Yes if there is a code for the VP or any other problem on the engine you should see the check engine light come on and stay on till code goes inactive or is fixed. Just have the dealership document the lift pump replacement and lack of pressure so if the Vp does go later and is close to warrenty you may have some ammo to throw at them.



Good Luck

Craig

 

[Sticks]

Originally posted by csevers

Yes if there is a code for the VP or any other problem on the engine you should see the check engine light come on and stay on till code goes inactive or is fixed.

This is not entirely accurate. You can get codes with out the check engine light. My VP44 was replaced due to a bad LP that I did not catch and the MIL never came on for the 4k miles that I kept getting the codes - 27 times, at least that is how many times I cleared the code.

 

[dieselsam59]

anyone else care to chime in on their experiences with vp44 testing?

 

[Sticks]

Roll some dice. More reliable than the dealers.



Dealer 1 said VP44 OK even though 0216 code kept showing up.



Dealer 2 said VP44 baked, and it killed the replacement LP. Both replaced under warranty.



Dealer mechanics are like doctors. Guess work in white lab coats, or in this case, a gray/blue monkey suit.

 

[A Johnson]

Originally posted by dieselsam59

anyone else care to chime in on their experiences with vp44 testing?

Most of our testing is done by process of elimination, i. e. nothing else can seems to be causing the problem so it must be the VP-44. The only "Cummins factory test" that we have is the tool that eliminates the wiring harness and engine ECM, to verify if the engine runs ok without the other electrics controlling it. There is also a go no go gauge out to test the pins in the VP-44 connector. Having said that there are a few things that can be done by some one with a little time on there hands and inginuity(sp). You can check how much vaccum a VP will pull while cranking, it should be 20"Hg or so with the inlet line deadheaded and achieve that number relatively quickly. You can check internal vane pump pressure, but I haven't done enough to give you good numbers. Because there are no published figures for these tests, the best way I've found to verify a test result, is to do the same test on a good running engine, and compare results.



Perhaps Evan Beck or some one else will chime in if they have developed any tests.



A Johnson