Evaporative Emissions System: Description and Operation

Evaporative System:

PURPOSE
The evaporative emission system prevents fuel vapor build up in the sealed fuel tank and vapors from being emitted into the atmosphere.

OPERATION
Fuel vapors trapped in the sealed fuel tank are vented through the vapor orifice rollover valve assembly. The vapors exit the valve assembly through a single vapor line and continue to the charcoal carbon canister for storage. When the engine has reached operating temperature and the throttle plate is past the idle position, the powertrain control module opens the control valve, allowing vacuum to be applied to the canister, purging it of stored fuel vapors into the induction system.