Evaporative Emission Control Canister: Description and Operation

EVAP Canister:

The Evaporative Emission (EVAP) canister is a sealed unit with 3 ports:
1. The purge pipe
2. The vapor pipe
3. The vent pipe

The canister is filled with carbon pellets that absorb and store the fuel vapors. The fuel vapor is stored in the canister until the powertrain control module (PCM) determines that the vapor can be consumed during the normal combustion process.