Fuel Tank Pressure Release Valve: Description and Operation

PURPOSE
Prevents fuel from escaping if the vehicle rolls over and controls fuel vapor transfer between the tank and canister.

LOCATION
Within the fuel gauge sending unit, in fuel tank.

OPERATION
When vapor pressure in the tank exceeds 5 kPa (1 in.Hg) the valve opens to allow vapor venting to the canister. When tank pressure is below the specified value, the valve closes and vapors are retained in the tank.