FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Evaporative Emissions System: Description and Operation




PURPOSE
Evaporative emission system prevents escape of fuel vapors to atmosphere under hot soak and engine off conditions. System also controls purging of stored vapors from charcoal canister to engine for burning.

OPERATION
System directs fuel tank vapors to the canister. Activated charcoal within the canister holds and stores vapors until they are purged into the induction system. The system is controlled by the powertrain control module, which operates the canister purge solenoid based on input signals from the engine coolant temperature sensor, the volume air flow sensor, and the camshaft position sensor.

CONSTRUCTION
System consists of a charcoal canister, canister purge solenoid valve, rollover/vent valve, two-way check valve and control system.