Just installed my holley fuel pressure regulator. Also, yesterday i wanted to test my new fuel pressure tester. Hooked it up to the schrader valve, primed the pump, and:

Needle went to about 20psi, then dropped back to zero as soon as the pump shut off. Same result after two more primes.

Once i got the car running, i have about 23psi.

Supposidly, fuel pump is new walbro 255. Im thinking fuel filter (which im going to do anyways). Could it be the regulator? Its brand new.

 

Why did you buy a new fuel pressure regulator and a fuel pressure test gauge? Did you have the same or similar problem with the previous regulator? If not, did you check the FPR vacuum compensation line for fuel? Check for signs of leakage around the FPR? Is the Holley FPR adjustable?

 

no signs of leakage around the regulator. I have not checked the vaccum line for fuel yet. It is adjustable, but i already increased the fuel pressure to its maximum. I never checked the fuel pressure with the stock regulator.

Only reason i put the holley one on is becuase it was included with the car, and i figured why not. I bought the test guage so i could monitor stuff like this.