Evaporative Emissions System: Description and Operation

The evaporative emission system prevents the escape of fuel vapors to the atmosphere under hot soak and engine OFF conditions by storing them in the evaporative emissions canister (EVAP canister). Fuel vapors trapped in the fuel tank are vented through two evaporative emission valves located on top of the fuel tank. Fuel vapors flow through fuel tank vent tubes to the evaporative emissions canister.

The stored fuel vapors are purged from the evaporative emissions canister to the intake manifold while the vehicle is being operated. The Powertrain Control Module (PCM) operates the evaporative emission canister vent solenoid allowing the stored fuel vapors to be drawn into the intake manifold for combustion.