The evaporative emission
control system prevents hydrocarbon (HC) vapors from the fuel tank from
escaping into the atmosphere where they could form photochemical smog.
Gasoline vapors are collected in the charcoal canister. The Canister Close
Valve (CCV) closes off the air inlet into the canister for leak detection
of the evaporative emission system. The CCV also prevents fuel vapors from
escaping from the canister. When the engine purges the HC vapors from the
canister, the clean air comes into the canister through the canister
air-filter and the CCV.
