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Fuel evaporation

Fuel evaporation



Evaporative emission canister

The evaporative emission canister consists of a container filled with activated charcoal, the purpose of which is to temporarily store fuel vapours from the tank and then release the vapours via the purge valve to the intake manifold for combustion.

The evaporative emission canister thus has hose connections to both the fuel tank and the intake manifold. It is also connected to the surrounding air which is drawn in via this connection and passed through the canister, carrying the fuel vapours with it into the intake manifold.

EVAP canister purge valve

The purge valve consists of a solenoid valve mounted on the hose between the evaporative emission canister and intake manifold.

The valve receives current from the main relay and is controlled from pin 36 of the control module with 15 Hz signals. The control module activates the purge valve as soon as the closed loop system is activated and engine temperature rises above 60°C (140°F).