Fuel Pump: Description and Operation

Transfer Pump System Component Locations:

Transfer Pump Location (Pump Concealed By Bracket):

Models equipped with 4-wheel drive have a fuel tank that is divided into two sections to accommodate the rear wheel drive shaft that runs under the center of the car. The fuel transfer pump, located under the car just ahead of the fuel tank, is used to move fuel from one side of the tank to the side where the main (high pressure) fuel pump is located. This ensures that the engine does not run out of gas when there is still fuel in the tank.

A float switch (part of the fuel gauge assembly) signals the fuel level to the transfer pump control unit. When the tank is just about empty, the float switch closes, grounding a terminal of the control unit. The control unit then interrupts the power to the transfer pump, turning the pump "OFF".

The transfer pump begins to operate ten seconds after the ignition is turned "ON", and operates continuously until the ignition is turned "OFF", or the fuel level in the tank drops below the level of the float switch.