Stock pump was dead when I bought the truck used. Second one died 5,000 miles later. Third one died 5,000 miles later. Now the four one is slowly dying with 3,000 miles on it. When new it was 13.5 psi at idle, 12 psi cruising & 10 wot. Now it's at 11 idle, 9.5 cruising & 7 wot. This has happened with all three that I have replaced except for the 2nd one, in which the pressure started jumping all over the place. I've changed the fuel filter with no change.

I'm was getting ready to order the Wildcat Max Flow Kit before the pressure started dropping. I'm also getting rid of the old style cylinder type fuel pressure isolator and running the line directly to the guage.

Any suggestions? I don't really want to spend the money for the FASS or RASP though.

 

Look for pickup problems between the tank and pump. You might also run rubber line in place of the hard line to try to sofen the pounding that pump takes. The line kit should help.

I have wondered if going to full 12v on the stock pump would help it some. Sure did help the FASS. If you should do that it starts fine so long as you let the wait to start light go out before starting.

I have planned to look into all this voltage stuff. The voltage is cut through the PCM, not the ECM. This is a Dodge thing. Wonder if the voltage is cut on the commercial engines. Don't forget, this engien and fuel system was designed for the commercial use and Dodge has modified it with all the tank garbage and PCM.

I have really wondered if the larger lines, straight 12 volts, and bottom feed or at least upgraded pickup would fix the lift pump problems with the stock pump.

 

Another thing I noticed today was when the truck warms up and I drive for a bit the idle pressure will top out at between 12 & 12.5. Seems after I run the truck for a while, ther pressure gets a little better. But I can still pull it down to 8.5 at wot. Why is this?

 

Mark, my fp was all over the place like you described (anywhere from 0 to 15). I was on my 2nd lp when it started going south. I got sick of it and obtained a Holley Black from my roommate and used 3/8" fuel hose from Napa to route it. $50 later and tweeking w/ the pump, my fp won't drop below 12, period. Screw the stock lp and replace it w/ a Holley. You won't regret it.

Hunter

 

HID, I am not so sure about the 12v issue, last time my LP started doing the eratic action(at idle), I put a volt meter on the connection at the pump, voltage was 11.97 and steady. Changed the pump from holley black to holley blue, problem solved. I will soon be adding a holley red at the tank, so the blue will have help, along w/a regulator.

 

could someone possibley list all items needed with pics so we can add the holley pupms.....+I'm irratic at idle also and worried i will have to spend another 1800.00 on another vp44....

 

Mines not irratic. It just gains a little pressure as it gets warmed up.

I just replaced the isolator and I gained about 1/2 psi all the way around. And from a stop to wot, the pressure doesn't drop as fast as it did with the isolator. I'm leaning toward the Max Flow Kit now.

 

Guess I should have said I removed the isolator altogether and went deirectly to the guage with fuel.

 

What is the upper limit on the fuel pressure that the system will accept. I have been looking at a fuel pump from Summit that runs around 18psi with a flow of 140gph potential. I thought of installing it close to the fuel tank and let it assist the factory LP without any other additions. It has a 3/8 in and out. Do you think that this would work without complicating the system as designed? It is a Summit brand.

 

I just discovered that my Lp is practically dead. I am still under warranty so I am going to have the dealer replace it, once it hits 100,000 miles though, its holley blue time.