hey guys. my buddy has a FASS on his dodge. it just started dropping the fuel PSI down to 3 and 4 when WOT. So we replaced the in line filter and the fuel filter hoping it would fix the problem, but it didn't. Doe it need some sort of adjustment? it idles at 15 fine, but cant keep up? help me out here. thanks

 

pull the return line fitting off clean the ball and spring thats behind it. What inline filter? What fass is on it?

 

its probably a HPFP from FASS...no filters just the pump.

i know there is a spring inside of them, how old is it?? maybe that spring is worn out.

 

I've heard of the springs breaking from fatigue too, come out in 2 pieces.

 

i have a fass hpfp and at idle its at 15-16psi and 4-5 psi WOT. stock filter housing with new filter and big banjo bolt kit. and a new inline filter i am running a mechanical fuel pressure gauge. can these pumps be turned up like the other fass pumps??

 

NO I dont believe so I have the hpfp 95 and was told no by the dealer where purchased.

 

i found out why i was getting low fuel pressure with my hpfp 95 fass pump. the overflow check valve on the injection pump return line was weak. so i bought a new one and helped alot. u can also take out the spring on the fass pump and stretch it about 1/4 longer and reinstall it just dont lose the check ball thats behind the spring. it adds about 3psi more

 

Many fuel pressure, performance, and starting problems have been caused by the overflow valve. Personally, I think it should be changed as part of a scheduled maintenance program. Once a year, or every 60,000 miles (100,000kms).

 

I pulled my ofv and put in one from TorkTek and my presssure went up and starting was better

 

can u explain installing the over flow valve and were its located thanks