My lift pump died on my 98.5 and I just replaced it with an airdog raptor pump. pump is pushing about 15psi on guage but truck will still not start.Should I crack several injectors and see if there is air in the injector pump. I had to remove fuel filter canister top get to lift pump so maybe air is in the injector pump or should I start to look at the injector pump and replacing?

thanks

 

ok got my truck running but when I bump the key the LP will run up to 15 psi but when truck starts it goes down to 0 do you have to turn up the pressure on these pumps when first installed or is there something else could be going on?

 

I usually crack 1, 3 or 4 then bump your fuel pump with the key trick to get the fuel pump to run for 30 seconds do this twice with key. Tighten up the injectors line and try to start run starter 20 seconds. Repeat if it does not start.

 

I know on the Holley you can stretch the spring or replace w/a diff spring. Not sure about the air dog but look for a screw adj or if there is a regulator built into it for adj

 

Not to be the debbie downer on this subject but you said the lift pump died? so I am assuming it just up and died or if you got a gauge you seen the pressures dropped.....Any way it may take several key bumps to get the system reprimed enough it will start,or you also may have more issue on your hands like along the lines of a dead injector pump..........

 

Regardless of the condition of your vp44, your airdog should still produce good psi. I have read about problems with these lately right out of the box.

I would check pressure with another gauge pre and post fuel filter and see what you have got.

If it is running on zero pressure, your vp44 is pulling fuel thru it, which is not good.

You may have a faulty or air trapped gauge, but check it out before you start driving it.

 

so key on it has 15 psi then truck running it has 0. what fuse did you tap to supply power?

i know with my fass i had it on a fuse that cut power while motor was cranking so i moved it to one that was on during the starting process aswell.