Evaporative Emissions System: Description and Operation
GENERAL INFORMATIONThe evaporative emission control system prevents fuel vapors generated in the fuel tank from escaping into the atmosphere.
Fuel vapors from the fuel tank flow through the fuel tank pressure control valve and vapor pipe/hose to be stored temporarily in the EVAP canister. When driving with a low to medium load (including while idling) on the engine, the fuel vapor absorbed by the EVAP canister is drawn into the intake manifold plenum.
When driving with a high load on the engine, the purge control valve opens and the fuel vapor absorbed by the EVAP canister is drawn into the air intake hose.
Furthermore, an EVAP ventilation solenoid is locate between the EVAP canister and the atmosphere in order to carry out OBD-II EVAP leak monitoring. This solenoid is normally off, but turns on during OBD-II EVAP leak monitoring to shut off the flow of air into the EVAP canister from the atmosphere. Also, fuel vent valve is provided at fuel filler tube to prevent fuel from being over-filling to a fuel tank.
SYSTEM DIAGRAM
FWD
AWD
COMPONENT LOCATION