No fuel getting past Fuel Pressure Regulator
Hello all. I have an interesting problem that maybe one of you guys can help me with. I have a r32 gtr with a R33 motor swapped into it. I am getting good fuel pressure to the rail, but nothing is returning to the tank. I have changed to a known good FPR from another car and get the same issue. I put a hose on the bottom of the FPR and still get no fuel at all coming out of the FPR. The car starts and revs good but only if I apply 12 volts directly to the fuel pump. But even with 12 volts going directly to the pump, I still get zero fuel return. I realize the fuel pump control module may be bad but that shouldn't have any affect on fuel return to the tank. I verified I have good vacuum going to the fpr with the motor running. The car seems to be running really rich(pulled plugs after only a few minutes of run time and they were black), I am guessing due to the fact that no fuel is getting past the fpr and probably overpressurizing the fuel rail(going to get a fuel pressure gauge and see what it is doing). I confirmed with another car that even with motor off and during the 5 seconds the pump turns on when you first turn on the key, there should be some fuel return to the tank. I have verified that none of the fuel lines are blocked or crimped. Any ideas as to why no fuel is getting past the FPR would be appreciated.