Evaporative Emission Control Canister: Description and Operation

Evaporative Control Canister:

PURPOSE
Store fuel vapor.

OPERATION
During periods of engine shutdown, the Evaporative Emission Control Canister stores vapors from the fuel tank in a charcoal media. When the engine has been started, and the coolant is above 75° C (167° F), the vapors are drawn out of the canister and burned in the engine.

CONSTRUCTION
Consists of a plastic canister filled with charcoal, having a vacuum controlled diaphragm on top that opens and closes the venting of the canister to the manifold.