Ok, listen to this guys. For the past week or so, my FP gauge has been acting up. When I start the truck up, idle is around 14-15 psi and WOT is no lower than 8 psi. I'll be cruising down the road then all of a sudden, the psi will jump down to 5 or so, give or take. I'll then accelerate and it will jump back up to 12 psi. Sometimes, it will jump back up, and sometimes it will drop down even farther. I'd say for a 10 minute cruise, it will do this "jumping around" for a solid 7 to 8 mins.

This current lift pump has no more than 6k miles on it, but thats what I'm thinking is going south. I've checked all my connections (electrical and mechanical) and everything is hooked up correctly, without leaks. I also have a needle valve on the fp hose.

My roommate has another mech. gauge and we're gonna hook that one up this weekend just to see if I have a faulty gauge. Any ideas guys?!?!?

P.S. I also installed a Comp after I have seen this jumping around, and it has no effect on my fp (I've unplugged it off for a few days and the fp gauge still acts up). No codes are set either.

 

Lift pumps have been known to be bad right out of the box, so very well could be.


phox

 

ttt

 

I just ran into the same thing on my truck. I had the pump replaced in May and then a few weeks ago the guage started jumping around like you described. Took the truck in and sure enough it was a bad pump, had it replaced at no cost.