EVAPORATIVE EMISSIONS (EVAP) CONTROL SYSTEM OPERATION


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• When the engine is stopped, evaporative gas in the fuel tank flows from the fuel tank as pressure rises, and is absorbed by the charcoal canister. Additionally, liquefied evaporative gas is stored in the catch tank.

• When the engine is running, evaporative gas absorbed by the charcoal canister together with air drawn from the atmospheric air port in the charcoal canister passes through the purge solenoid valve and is then inducted into the engine in an amount appropriate to engine condition.

• If negative pressure in the fuel tank rises, air is drawn from the charcoal canister atmospheric air port via the rollover valves. If the atmospheric air port in the charcoal canister becomes clogged, this malfunction causes negative pressure in the fuel tank to rise, applying a load to the fuel tank, and the negative pressure valve in the fuel-filler cap opens to draw air into the fuel tank.