Also known as the Emission Control Canister Purge Solenoid, the Vapor Canister Purge Solenoid/Valve allows fuel vapor flow from the EVAP system. It transfers fuel vapors stored in the vapor canister into the engine's intake system by opening and closing as commanded by the engine's computer system. The solenoid is normally closed to prevent fuel vapors from entering the engine during a non-purge condition.
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The vent solenoid, located near the EVAP canister inside a wheel well or under the vehicle near the fuel tank, usually fails before the purge solenoid. The purge solenoid will fail closed or will fail by sticking partially open illuminating a check engine light. When illuminated, common failure modes are:
Electrical failure of the purge valve control circuit
Electrical failure of the purge solenoid
Vacuum line leaks
Plugged vacuum line
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