Fuel Tank Pressure Release Valve: Description and Operation

PURPOSE
The Fuel Tank Pressure Relief Valves are located in the fuel filler cap. Two safety valves prevent damage to the fuel system in the event of damage or blockage to the fuel tank venting system or it's hoses.

OPERATION
One Fuel Tank Pressure Relief Valve opens in the event of fuel tank over-pressure, the other Pressure Relief Valve opens in the event of excessive vacuum within the fuel tank or the tank venting system.