Fuel Pump: Description and Operation

Fuel Tank Assembly (4WD Only):

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. A low pressure electric pump (fuel transfer pump), is used to move fuel from the right side of the fuel tank to the left side, where the main (high pressure) fuel pump is located.

The transfer pump, like the main fuel pump, is installed in the fuel tank. Removable covers, located under the rear seat cushion, provides easy access to both pump assemblies, without removing the tank.

Transfer Pump Tank Unit Assembly:

Removing 4X4 Control Unit:

A magnetic float switch (part of the transfer pump/gauge assembly) signals the fuel level to the 4X4 control unit (which controls transfer pump operation). The control unit has a timer built in, so the transfer pump doesn't begin to operate until approx. ten seconds after the ignition is turned "ON". Once turned on, the transfer pump operates continuously until the ignition is turned "OFF", or the fuel level in the tank drops below the level of the float switch. 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" to prevent damage from running "dry".