How affective might a new fuel pressure regulator be for Gas mileage?

[jessetruitt3]

I have a 2000 Grand Prix GT, non-supercharged 3.8.  When i first bought my car 3.5 years ago, it could get over 425miles per tank. Shortly after and since then I can only get about 325 max.  I've installed new plugs,wires,fuel filter,mass air flow sensor,air filter, and use Full synthetic Mobil 1 oil. I haven't gone cheap on these parts and still I can't get back up to 400+miles.  I've heard that either a new fuel pressure regulator, or new O2 sensor would increase mileage. Does anyone have any good advice?

[dodge man]

have the computer scanned on it first adding things to it that it might not need wont make it get better gas mileage if it doesn't need them,id have a scan done on it and see what the results are from it,good luck.

[Mark Z]

The main job of the fuel regulator is to regulate the pressure in the fuel system to a standard constant of 28 psi. To accomplish this task, the gadget employs a diaphragm, which controls the valve. Excessive pressure in the line will open this valve up and release the fuel but will push back excess gas to the tank.

The regulator's vacuum also helps decrease emissions as the car halts. When deceleration occurs, the vacuum opens the valve where the fuel is returned to reduce the pressure in the system. This helps prevent excessive production of hydrocarbon since there is less fuel being injected due to the low pressure.

turborevs.org.uk