Every 38,000 km or every two years.
The EVAP system has the function of removing fuel vapors from the fuel tank and fuel system, concentrating them in a charcoal canister, and then burning them during normal engine operation. Usually this system is installed only on vehicles equipped with catalytic converters.
The most characteristic symptom of a malfunction in the evaporative emission system is a strong smell of gasoline in the engine compartment. If you smell such a smell, inspect the carbon canister and hoses (arrow) systems for cracks. The adsorber on most models is located in the front corner of the engine compartment.
For more complete information on the system of catching fuel vapors, please refer to the Chapter Engine management and emission control systems.