Mustang Vapor Canister Purge Valve
The Evaporative Emission (EVAP) canister purge valve is in-line with the evaporative emissions canister and controls the flow of fuel vapors out of the evaporative emissions canister. The EVAP canister purge valve is normally closed. When the engine is shut OFF, vapors from the fuel tank flow into the evaporative emissions canister. After the engine is started, the evaporative emission canister purge valve is engaged and opens, purging the fuel vapors into the engine. With the evaporative emission canister purge valve open, vapors from the fuel tank are routed directly into the engine.