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 rear suspension cross member and is connected by pipelines to the fuel tank and the purge solenoid valve.

The adsorber purge solenoid valve, which switches the system operating modes at the signals of the engine control unit, is located in the engine compartment.

Fuel vapors from the fuel tank are constantly discharged through the pipeline and accumulate in the adsorber filled with activated carbon (adsorbent). When the engine is running, it periodically regenerates (recovery) adsorbent by blowing the adsorber with fresh air from the atmosphere.

Air enters the system under the action of a vacuum transmitted through the pipeline from the intake manifold to the adsorber cavity when the purge valve installed in the pipeline is opened. The electronic engine control unit regulates the intensity of the adsorber purge depending on the engine operating mode, supplying a signal to the valve with a variable pulse frequency.

Fuel vapor from the adsorber through the pipeline enters the engine intake pipe and burns in the cylinders.

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