Fuel Tank Venting

Fuel vapor generated from within the fuel tank as the fuel heats up is stored in the tank until the pressure exceeds the operating pressure of the two-way valve. When the two-way valve opens, the fuel vapor passes along the vent line from the fuel tank via the fuel tank vapor separator to the evaporation inlet port of the charcoal canister.

Liquid fuel must not be allowed to contaminate the charcoal in the EVAP canister. To prevent this, the fuel vapor separator fitted to the fuel filler neck allows fuel to drain back into the tank. As the fuel vapor cools, it condenses and is allowed to flow back into the fuel tank from the vent line by way of the two-way valve.

The charcoal canister contains charcoal pellets which absorbs and stores the fuel vapor from the fuel tank while the engine is not running. When the canister is not being purged, the fuel vapor remains in the canister and clean air exits the canister via the air inlet port.