Fuel Tank Unit: Description and Operation

Fuel Sender Assembly:

Fuel Pump And Reservoir Fuel Flow:

FUEL TANK UNIT
The fuel tank unit is located inside the fuel tank and is attached to the top of the fuel tank.
The fuel tank unit consists of the following major components: a fuel sender, fuel pump and reservoir assembly, and a fuel pump strainer.

Fuel Sender Assembly
The fuel sender consists of the float, wire float arm, sensor and roll-over valve. Fuel level is sensed by the position of the float arm, and a signal is sent to the display in the vehicle instrument cluster.

Roll-over Valve
The roll-over valve is pressed into the Evaporative Emission (EVAP) pipe of the fuel sender and is not serviced separately. The roll-over valve prevents fuel from spilling from the fuel sender EVAP pipe if the vehicle rolls over.

Fuel Pump And Reservoir Assembly
An electric high pressure roller vane fuel pump is mounted inside the fuel reservoir, which is located in the fuel tank. The fuel is pumped to the fuel rail assembly at a specified flow and pressure by the fuel pump. Excess fuel is returned to the fuel tank by the return pipe. The electric fuel pump operation is controlled by the Powertrain Control Module (PCM) through a fuel pump relay.

Fuel Pump Strainer
A woven plastic fuel pump strainer is attached to the lower end of the fuel pump and reservoir assembly in the fuel tank. The functions of the fuel pump strainer are to filter contaminants and to wick fuel.

The life of the fuel pump strainer is generally considered to be that of the fuel pump. The fuel pump strainer is self-cleaning and normally requires no maintenance. Fuel stoppage at this point indicates that the fuel tank contains an abnormal amount of sediment or water. In this case the tank should be thoroughly cleaned. If the fuel pump strainer is plugged, replace it with a new fuel pump strainer.