Engine/Transmission (1998.5 - 2002) Fuel Pressure?

[6smokin]

My Fuel pressure has always been around 10+. I look over at my guage and notice that the fuel pressure is at 3!! In the thought that usually when i hit the go fast pedal the fuel pressure goes down, so i did just that put the hammer down and to my surprise the fuel pressure started to rise. Is this a malfunctioning guage or a lift pump promblem? Any and all advice would be appreciated.



Cody

 

[6smokin]

I realized i forgot to mention what has been done to my truck. 02 ext cab 4x4 scheid lightning turbo, lightning 1 injectors, fuel pump relocated w/1/2" fuel lines, boost, egt, and fuel pressure guages... No Isolator on the fuel pressure guage. I also have a short throw shifter and a SBC DD 3600 12 ceramic buttons.

 

[Graphic man]

either the pump is shot or it's time to replace the fuel filter

 

[6smokin]

The lift pump is still working. I Don't know a whole lot about the way the LP's work. If the pump kicks on does that mean its still working fine?

 

[AWeik]

id try bleeding the line to the gauge. i had to bleed mine a few times before it was consistant. i never noticed any pressure changes at idle or WOT, but now the gauge doesnt dive at random.

just because you hear the LP running doesnt mean its still good either. i replaced my LP over the summer and added the vulcan big line kit about a month ago, just this monday the Cummins replacement part died though it still sounded haealthy. i put the stock LP back in its place with the same pressures having 103k on it... . My . 02











AFW

 

[6smokin]

Thats whats weird is i didn't install the guage, it was in the truck when i bought it and has worked fine for almost a year. Could somthing have changed?

 

[mhenon]

Thats whats weird is i didn't install the guage, it was in the truck when i bought it and has worked fine for almost a year. Could somthing have changed?

It doesn't matter who installed the gauge. . it can still be the problem. Have it checked out for air as this can cause strange readings.

Mike

 

[6smokin]

Alright ill try that. I appreciate all the help.



Thanks, Cody

 

[PMalin]

I recently "checked" my lift pump while doing a filter change. 2001 truck. With the top off the filter canister, and after I cleaned the canister out and having drained out the fuel in it. Then to fill the canister, bump the starter and the lift pump will cycle on for appx 20 seconds. Usually the canister fills with fuel and a little spills over. But this time there was no fuel filling the canister. I could clearly hear the lift pump running. So a lift pump can make sound of the electric motor spinning but the acutal pump may not be working at all. I replaced the LP at noticing this. Fixed my FP gage and now seeing about 13psi, oh and the canister fills up well now.