Evaporative Emission System

The fuel vapor recovery system prevents the release of fuel vapors from the power supply system into the atmosphere, which adversely affect the environment.

The system uses the method of vapor absorption by a carbon adsorber. It is mounted on the right side of the fuel tank bracket and is connected by steam lines to the fuel tank and inlet pipe. On the bracket mounted on the inlet pipe, there is an adsorber purge solenoid valve, which switches the operating modes of the system according to the signals from the engine control unit.

Fuel vapors from the fuel tank are constantly discharged through the steam line and accumulate in the adsorber filled with activated carbon (adsorbent). When the engine is running, it regenerates (recovery) adsorbent by purging the adsorber with fresh air entering the system under the action of vacuum, transmitted through the steam line from the inlet pipe to the adsorber cavity when the valve is opened. The magnitude of the valve opening and the intensity of the purge of the adsorber depend on the angle of rotation of the throttle valve and are determined by the vacuum that occurs in the cavity of the intake pipe of a running engine.

Fuel vapors from the adsorber through the steam line enter the engine intake pipe and burn in the cylinders.

Malfunctions of the fuel vapor recovery system entail idle instability, engine shutdown, increased toxicity of exhaust gases and deterioration in driving performance of the vehicle.