Toyota 77740-47060 CANISTER Assembly, CHARC

The fuel evaporative emissions control (EVAP) system absorbs fuel vapors and releases them into the engine intake during operation, where they mix with the incoming air-fuel mixture, with the charcoal canister mounted above the fuel tank. When the engine is off, fuel vapors are stored in the charcoal canister, and when running, they are purged by the purge control valve, with the electronic valve controlled by the ECM. A two-way valve on the fuel filler cap vents vapors to the atmosphere if the EVAP system fails, while a vapor pressure sensor on the fuel tank detects abnormal pressure. After the engine warms up, the vacuum switching valve opens, allowing intake manifold vacuum to draw vapors from the canister for combustion. The vapor pressure sensor monitors tank pressure and opens the vacuum switching valve when a preset threshold is exceeded. For replacement of the charcoal canister, disconnect the negative terminal of the auxiliary 12-volt battery and lower the fuel tank to access the canister. Unplug electrical connectors, label and disconnect vent hoses, remove bolts, and separate the canister from the vehicle, with installation being the reverse of removal.

During the inspection, the canister and all hoses should be checked for damage and deterioration.