how can i tell if my fuel pressure regulator is bad??
 

Ive had the same FP regulator for a few years now, and was thinking it might be bad?? When I first start the car it can be as high as 8-9 and go down to below six after soo long. This doesnt make sense since im using a Holley Black series elec pump and isnt relative to RPM as a mech. style is. The voltage to the pump also doesnt change since its on a relay directly to the battery. I also use a return line so I doubt I have vapor lock at over 100GPH.
The only other thing i could think might be causing it is needing a higher flow fuel filter

Chris

Re: how can i tell if my fuel pressure regulator is bad?? (74VETTE)
 

I am fighting the same problem now, I called Holley and they said it is the check valve in the pump. I have dual Holley blue pumps. They siad to take the brass screw / plug out of the side of the pump and clean it real well. I have not had time to do it yet.

Re: how can i tell if my fuel pressure regulator is bad?? (69 N.O.X. RATT)
 

Thats BS if its the truth....my pump is less than a month old and i run a filter right before the pump and its clean as can be. Not that it cant be true...but pretty bad on Holley's part if it needs cleaning already....Ill have to give it a try tho....thanks for the reply 69 N.O.X. RATT

Re: how can i tell if my fuel pressure regulator is bad?? (74VETTE)
 

Both of my pumps are doing it. My pumps are 10 years old, but I have only been using them for a little over a month. I thought my problem was that they sat on a shelf for 10 years before I used them.

Re: how can i tell if my fuel pressure regulator is bad?? (69 N.O.X. RATT)
 

I guess its the curse of a month....kinda like the one year mark with a girfriend when the :boxing starts....LoL

let me know how it works out if you clean it.
What kind of filter are you using??

Re: how can i tell if my fuel pressure regulator is bad?? (74VETTE)
 

I am going to clean both of them, can't use the NOS when I have fuel pressure problems. I am using big canister filters of trucks.