Fuel Pump Control Unit

Fuel pump control unit is located on right side of trunk compartment. Based on signals from ECM, control unit regulates voltage supplied to fuel pump. By increasing or decreasing current flow through fuel pump, fuel volume can be adjusted to one of 2 levels (high and medium).

High voltage (battery voltage) is applied to fuel pump during the following conditions: engine cranking, engine operation when coolant temperature is less than 50°F (10°C), and high-speed operation or heavy engine load. This produces maximum volume.

During middle load and middle speed conditions, medium voltage (8 volts) is applied to fuel pump. This produces medium fuel volume. During all other modes of operation, low voltage (5.6 volts) is applied to fuel pump, providing minimum volume. Fuel pump control unit is operated by ECM.