SVX L6-3.3L DOHC (1992)
Fuel Pump Control Unit: Description and Operation
System Operation
Fuel Pump Control
PURPOSE
Reduces evaporative gas generation in the fuel tank.
OPERATION
Fuel returning to the fuel tank causes evaporation gas to form. This system lowers fuel discharge volume so less fuel is returned to the fuel tank,
thereby reducing evaporation gas.
^ At low engine speeds, the source current flows directly through the fuel pump to ground and the pressure discharge reate remains constant,
^ As engine speed increases, the ECU sends a signal out to the modulator to allow the source current to flow through the modulator and resistor to
ground.
In this way, the amount of current flowing through the fuel pump varies with engine speed, thus fuel pump discharge is controlled.