Engine/Transmission (1998.5 - 2002) fuel pressure

[duckcarvr]

I have 14 psi pump in front of my fuel tank plus the one on the engine. at idle i have 19-22 psi. i called bd and they said if both pumps are working well, to gether i should have 28 psi. it would seem then that the engine fuel pump is putting out at least 6 psi. if i take the fuel pump in front of tank off line i have 0 psi. in 3rd gear [auto] at 60 mph i have 10-12 psi. shift to o/d and i have 15-16 psi. could this be the location they hooked the pressure gauge? or should i just put a new pump on engine? thanks robert

 

[Bob4x4]

If you are just removing the power from your frame mounted pump and not removing it from the line it can be a restriction.
The Vp trucks do not like to start at over 20 psi. Not sure what your concern is??

 

[JR]

I dont think its a good idea to be running 2 pumps in tandem like that. I f you have a frame mounted aftermarket pump (not in the tank) I would completely bypass the stock frame mounted pump. You could leave it there for a back up if you want, just run the lines around it with provisions to hook it back up in the event your other one fails. I run my fp gauge right off of the top of my fuel canister. I think yours may be different than mine, you may have to tee into the line between the canister and the vp.

 

[duckcarvr]

thanks for responding guys. i bumped the starter today and it held at 7 psi. would you run with a pump that low? when i start the truck fuel pressure gos to 0. 4x4 my second pump is started when oil pressure comes up 10-15 seconds later so its not starting at 20 plus psi. BD says both pumps are designed to flow through with little or no restriction?? my concern was the 0 psi after it starts till second pump kicks in. i guess i will take your advice and go around the pump on the engine but i will put a new one on . but i liked that extra psi. lol thanks again robert

 

[JR]

If your fp goes to 0 after starting, i would think that pump is shot? Or maybe its not able to pull or push (depending on which pump kicks on first) through the pump thats off? You mentioned the manufacture recomends running them in tandem like that, i would listen to them over me im not familiar with which pumps your running. What fuel pressure do they recomend you run with one and then both pumps running?