Evaporative Emissions System: Description and Operation

PURPOSE
The Evaporative Control (EVAP) system, to reduce HC emissions, prevents the escape of fuel vapors from the fuel tank and the fuel injection system into the atmosphere.

OPERATION
Vapors generated in the fuel tank enter the charcoal canister where the charcoal absorbs and stores the fuel vapor. When the Programmed Fuel Injection Electronic Control Module (PGM-FI ECM) determines the correct conditions for operation, it cuts the ground circuit to the solenoid. This opens the solenoid, allowing manifold vacuum to be applied to the carbon canister, causing fresh air to be drawn into the bottom of the canister. The vapors then pass through the solenoid valve into the intake manifold to be consumed in the combustion process.