By the way it is called a "Dual Function Reservoir" - 9B263 (base part number) and not a "selector valve". The "Dual Function Reservoir" is not electrically powered, it operates off the fuel pressure of the running fuel pump.
There's no "real" selector valve on 1990-1996 trucks. The older 1987-1989 and 1986 5.0L EFI trucks have a dual function reservoir mounted on the frame rail that acts like a selector valve. The Carbonated trucks 1985 and earlier 5.0L and 1987 and below 4.9L, 5.8L and 7.5L have a 6-way mechanical valve. The switch on your dash selects which fuel pump will be energized.
Last edited by subford; 03-24-2006 at 06:21 AM.