Fuel Tank: Description and Operation

FUEL TANK
The fuel tank is constructed of a plastic material. Its main functions are for fuel storage and for placement of the fuel pump module, and certain ORVR components.

All models pass a full 360 degree rollover test without fuel leakage. To accomplish this, fuel and vapor flow controls are required for all fuel tank connections.

A check (control) valve is mounted into the top section of the 2-piece fuel pump module. Refer to Fuel Tank Check Valve for additional information.

An evaporation control system is connected to the fuel tank to reduce emissions of fuel vapors into the atmosphere. When fuel evaporates from the fuel tank, vapors pass through vent hoses or tubes to a charcoal canister where they are temporarily held. When the engine is running, the vapors are drawn into the intake manifold. Certain models are also equipped with a self-diagnosing system using a Leak Detection Pump (LDP) and/or an ORVR system. Refer to Emission Control System for additional information.

Fig.1 Fuel Delivery Components:

FUEL TANK CHECK VALVE
The fuel tank is equipped with a check valve The valve (also referred to as a control valve) is located in the top section of the fuel pump module assembly.

The fuel tank check valve (also referred to as either a control valve, one-way check valve or float valve) will prevent fuel flow through the fuel tank vent in the event of an accidental vehicle rollover. It is also used as a part of the ORVR system. The EVAP canister and ORVR system draw fuel vapors from the fuel tank through this valve. Refer to ORVR in Emissions for additional information.

The valve may be serviced by replacing the upper section of the fuel pump module assembly.