97' 12 valve will not rev

[backcountry]

Hey guys I have a 97 12 valve with about 150k on it and all of a sudden one day it just stopped reving. It starts up great and idles great but around two thousand rpm's it just drops off. It seems like it might be a fuel problem but I'm just not sure. replaced the fuel filter and the fuel shut off solenoid, and relay but it's still doing the same thing. Any help would be greatly appreciated. Also it's not building much boost before it dies. Maybe around ten of fifteen psi.

 

[Whit]

replace the small fuel hose from the back side of the IP to the steel line comming from the lift pump..............yer prolly suckin air ..........very common this hose cracks and wont leak fuel but will suck in air ......sounds wierd huh

 

[nevrenufhp]

Either sucking in air, or restricted fuel line. Also check the pre-filter screen next to the lift pump, it can clog up with goo.

 

[backcountry]

I replaced the small fuel line to the IP, and also cleaned the pre-filter. The problem got a little better but is still doing it. Now the truck wants to die if you let off the throttle right after you get on it. Also seemed like it got worse when locking the torque converter. I dunno. ^Thanks for the help^, but if you have any more suggestions it would be greatly appreciated. Scott

 

[Pipeliner_86]

A freinds truck did this a few years ago. His turbo was going south. Maybe check out your turbo.

 

[backcountry]

Well we put a new lift pump on and it started running like a dream again....for about fifty miles, now it seems to be starving of fuel again, and or sucking air. we replaced the rubber fuel lines, and fuel shutoff solenoid. The fuel line coming out of the lift pump is clear and looks like it has quite a bit of air bubbles in it. Should i remove the fuel heater as well? Also when pushing the primer button on the lift pump you can hear something almost whistle around the injection pump. Is this just the check valve?

 

[Whit]

go fill the tank full and see how it acts...................you may have a pin hole on the line inside the tank, with a full tank the hole wont matter so it will prove the theory

if this is the problem then you need to drop the tank and clean the crap out and install a draw straw pickup tube