[CMMINS]

I installed a needle valve between the filter housing and the VP-44, with a tee and when i crack open the needle valve it sucks fuel from the gauge? any suggestions on how i can fix this issue?

 

[Ops]

Sounds like you already have a dead lift pump, the fuel line should be under pressure, not a vacuum.

STRONGLY suggest that you install a frame mounted pump like a Holley Blue or Airdog before you roast your VP.

Ops

 

[dieseldude5.9]

X2 with Ops, you need an aftermarket lift pump

 

[carl48]

you did not get the gauge on fast enough bet you are going to get a new vp-44 shortly

 

[CMMINS]

You were right, replaced the lift pump and now the gauge shows 14 psi at idle.
Thanks :$:

 

[package60]

CMMINS, did you check for any codes after you replaced your lift pump?

Turn your key on and off and the third time leave it in the on position. Look by the odometer there will be dashes that scroll by or numbers if you have a code. Hopefully you caught it fast enough that the VP didn't get compromised.

 

[totalloser]

I am guessing that with 14 psi, you got an aftermarket (stock is usually run between 5 and 10psi) but if you didn't it's not good enough.

The factory lift pump is, well, just in a bad location. It has to prime from dry, that's why they wear out. But another thing is that the relay that controls it is inside the PCM (I'm pretty sure) and the aftermarket setups do two things to correct these problems. 1. Mount the second/aftermarket on the framerail where they don't lose their prime. 2. Operate off a seperate relay taking the load off the PCM relay so you don't have to replace your PCM or crack it open to replace the relay. At least get a relay between the factory power and the lift pump.

By the way, the reason you got an actual vacuum is that there is a diaphragm pump inside the vp that helps move the fuel. It is not adequate on it's own, though. At least that's the way I understand it.