EVAP Purge Valve
An electronic solenoid valve that regulates the flow of stored fuel vapors from the EVAP canister into the engine's intake manifold.
The EVAP purge valve (or canister purge solenoid) is an electronically controlled valve that manages the "purging" of fuel vapors from the charcoal canister. Under specific driving conditions, the engine control module (ECM) energizes the solenoid, opening the valve and allowing engine intake vacuum to pull stored vapors out of the charcoal canister and route them into the combustion chambers.
If the purge valve sticks open, it creates a constant vacuum leak, allowing excess fuel vapors into the engine, which causes a rough idle, hard starting after refueling, and a rich fuel mixture. If it sticks closed, the EVAP system cannot vent, leading to built-up pressure in the gas tank and diagnostic trouble codes (such as P0441 or P0442) that illuminate the check engine light.
Replacing a faulty purge valve is a common, inexpensive repair that resolves many EVAP codes.