Ok guys, I don't mean to be stupid but I am confused about what the VP44 is. Is it the injector pump or is it a valume pump on the injector pump. please help me understand because I am having trouble with my truck and would like to fix it. sounds like ya,all know what your talking about. I have read the threads about fuel pressure. Mine only reads 11 psi at idle and only 7 to 8 at 70 mph. I feel like hear lateley im loosing power and the truck wants to buck a little under a load. I own a 2001 2500 H/O with a six speed trany. I have added a bigger turbo and a 14cm nonwastegate housing and edgebox EZ. It used to run real strong and puff the black smoke that tells me its fueling good but now it don't smoke to bad. Can anyone tell me whats going on. thanks for your input. A dumb .

 

What year is your truck?

The VP44 is the large injection pump that all the hard lines from the fuel injectors connect to.
The lift pump is the smaller pump on the driver's side of the block back near the starter that supplies enough fuel from the tank to the Injection pump to provide the fuel to run as well as the excess fuel which is used to cool the injection pump and then, returned to the tank.




Number 1 is the Lift Pump.

Number 17 is the VP44

 

Unplug your EZ and see how it runs. I've had two go bad on me. The first one stopped smoking, the second one smoked too much, and the third one is juust right. (Hmmm....sounds the the three bears)

 

Thanks for your reply sounds like I have some money to spend. Does the pump in the tank supply the Vp44 and is the reason for my low fuel psi readings.

 

There is no pump in the tank on that vehicle. The lift pump is probably the culprit if you are having pressure issues. See the diagram listed earlier in the thread. There is a pickup screen in the tank however and it gets clogged sometimes.

 

Unless you've had one installed, you don't have a pump in the fuel tank. The lift pump (#1) determins your fuel pressure