Evaporative Emission (EVAP) Canister Vent Valve
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The EVAP canister vent valve (located in the EVAP canister dust box) is part of the enhanced EVAP system controlled by the PCM. During the EVAP leak check monitor, the EVAP canister vent valve seals the EVAP canister from the atmospheric pressure. This allows the EVAP purge valve to achieve the target vacuum in the fuel tank during the EVAP leak check monitor.