Fuel Vapor Vent Valve (FVVV): Notes
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The FVVV is a PCM controlled solenoid that isolates the fuel tank from the rest of the EVAP system. The PCM opens the FVVV during refueling to allow the flow of vapors from the fuel tank to the EVAP canister. The FVVV will automatically open to relieve excess pressure if the fuel tank pressure reaches a maximum mechanical relief threshold value.