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Evaporative emission canister

Evaporative emission canister


The EVAP canister is situated behind the tank and comprises a container filled with a special type of carbon pellets. Pellets are used so that the counter-pressure from the EVAP canister is kept as low as possible. Hydrocarbons that evaporate in the tank are carried to the EVAP canister where the active carbon gradually becomes saturated as it absorbs the hydrocarbons.

The fuel tank, EVAP canister purge valve and shut-off valve are all connected to the EVAP canister. When the engine is started, air is sucked through the shut-off valve to the EVAP canister and then via the EVAP canister purge valve into the intake manifold taking with it the hydrocarbons that are then burnt in the engine.

The EVAP canister absorbs approx. 80-90 grammes of hydrocarbons each time the tank is filled. When the car is running, the EVAP canister is purged, the time this takes depending on how the car is driven. The EVAP canister can absorb max. 150 grammes of hydrocarbons.