My car has a hard start after the car has warmed up. Cold start is great. However, I have changed the OVP, fuel distributor, injectors, check valve, accumulator, and fuel filter. The only thing I have not changed is the fuel pressure regulator. I am also getting horrible gas mileage.

I am wondering could the fuel pressure regulator be damaged and not let fuel return to the tank and when the car is off cause the fuel to boil or lead to too much pressure in the fuel lines?

Any help would be great.