My vp is on the way out, I'm about to replace it. I've got a holley blue without the regulator under the bed pushing fuel up, a Big Line kit from the fuel filter to the IP. I'm about to order a vp44, and could use some suggestions on best brand/reliability etc.

I'm currently running approximately 13 psi at idol. I can draw it down to a minimum of 9.5 if i mash it. When i turn the key and wait to start, my fp goes up to about 4, and then bleeds off to approximately zero according to my gauge. Is that expected? Could this have caused the IP to begin to fail? how about trying to get the engine started with gelled fuel? Could that have been partially responsible for the failure? I know that the service manual states that there should be a minimum cranking psi, so my question is why is mine bleeding off? While i'm replacing the vp44, what else should i order while i'm at it?

 

Thats normal.

 

The LP only runs for a second when the key is first turned on (more or less depending on which software version you have in your ECM). The LP does not run during startup as the VP44 sometimes has hard start issues if you have positive inlet pressure while cranking. The LP doesn't begin running till the engine does.

 

So its normal to bleed off to zero before it starts?

 

Yea its normal. My attitude beeps at me for low fuel press almost everytime at start up but jumps up to 20 psi in a half second once its running.

 

Yeah, there are no check valves or anything to hold pressure in the system, so as soon as the pump stops, the pressure bleeds off.

 

yep its normal, Why are you replacing the VP? is it throwing codes?

 

Yeah I've got 0216 and dead pedal

 

[QUOTE=dhughe2;2533651]My vp is on the way out, I'm about to replace it. I've got a holley blue without the regulator under the bed pushing fuel up, a Big Line kit from the fuel filter to the IP. I'm about to order a vp44, and could use some suggestions on best brand/reliability etc.

http://www.industrialinjection.com/

 

I know nothing about the fuel pressures since I don't have a gauge but the lift pump in my 1999 pusher RV rig starts running the instant the starter is engaged. It continues to operate for 20 seconds or so even if the engine does not start. It will continue to run for the 20 seconds even if the key is immediately turned to the off position after bumping the starter. It does not operate when the key is turned on. The starter must be engaged - even if bumped just a little - before the lift pump operates. It continues to operate all the time the engine is running. Don't know, it might be different on the pick ups.

 

That's the same process used on the trucks. If you only turn the key on, the lift pump with run for 0.5-5 seconds (depending on which flash you have in the ECM). If you bump the starter, then the lift pump will kick in and run for about 45 seconds to prime the system. They did this so you have a way to prime the system after a FF change or any other time you lose prime since there is no manual priming lever like the 12Vs. It will run it's full cycle even if you turn the key off.