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6.4. Systems of release and decrease in toxicity of the fulfilled gases

General information

System of release

Within recovery repair each section of system of production of the fulfilled gases can be replaced in an individual order.

System of decrease in toxicity of the fulfilled gases

Petrol models

In power supply systems of all petrol models only unleaded gasoline has to be used!

The principle of functioning of a control system of the engine is constructed so that to receive the maximum return from the engine at the minimum fuel consumption and the maintenance of toxic components in the fulfilled gases. The system of catching of fuel evaporations prevents hit of the last of the fuel tank in the atmosphere. Also the system of recirculation of the fulfilled gases is installed.

System of the operated ventilation of a case (PCV)

For elimination of leak of not burned down hydrocarbons in the atmosphere the engine is completely sealed. The gases and vapors of oil which are formed in a case via the mesh filter get to the inlet pipeline and burn down in cylinders together with fuel.

Gases are removed from a case at the expense of pressure difference in a case and the inlet pipeline (pressure in a case is higher).

System of recirculation of the fulfilled gases (EGR)

The system of recirculation of the fulfilled gases allows to reduce the number of NO X in the fulfilled gases. For this purpose a small part of the fulfilled gases moves in the inlet pipeline via the special valve. The valve of system of recirculation is run by the control unit.

System of catching of fuel evaporations (EVAP)

For decrease in emission in the atmosphere of not burned down hydrocarbons on all petrol models the system of catching of fuel is installed. The filling mouth of the fuel tank is hermetically closed by a cover, under the fuel tank the coal adsorber is established. In it the fuel vapors which are formed in a tank during the parking of the car gather and are stored there until on a signal of the control unit the filter purge does not begin. Then vapors of fuel begin to move via the purge valve(s) in the inlet pipeline, there they mix up with working mix and further burn down usually in combustion chambers.

For ensuring normal operation of the engine on single turns and during warming up the control unit holds the valve closed. Thus hit of not burned down fuel in the converter (is prevented at the raised idling turns mix of a pereobogashchen). After warming up of the engine the valve begins to open and be closed, giving fuel vapors to an inlet path.

Catalytic converter and lambda probes

For decrease in number of harmful emissions in the atmosphere on all petrol models the three-functional catalytic converter is built in system of release. The control system of injection of fuel has feedback which switched on the oxygen sensor. This sensor installed in system of release constantly informs the control unit on composition of the fulfilled gases. Depending on the obtained data, the control unit corrects quality of the mix given to combustion chambers and, thus, optimizes fuel combustion.

In a lambda probe the heating element which is switched on by the control unit via the special relay is built in. The working surface a lambda probe is sensitive to change of content of oxygen in gases. Depending on concentration of oxygen, the sensor sends signals of different tension. If mix of a pereobogashchen - the content of oxygen in the fulfilled gases very low, the sensor gives signals with low voltage. Tension increases in process of impoverishment of mix and increase in content of oxygen in gases. Most effectively the converter works at optimum composition of gas mixture (14.7 parts of air for 1 part of fuel). At change of concentration of oxygen in the fulfilled gases near optimum value there is a power surge of the sensor. This jump is a reference point for the control unit at correction of quality of mix.

Two sensors are installed: one - before, and the second - after assembly of the catalytic converter. It reaches more exact tracking of composition of the fulfilled gases.

Diesel models

The same requirements, as at petrol units are the basis for the principles of functioning of a control system of the diesel engine. For additional decrease in toxicity of gases on the car several auxiliary systems are installed. The system of ventilation of a case reduces leak of gases in the atmosphere from the engine lubrication system. The catalytic converter reduces toxicity of the fulfilled gases. The system of recirculation of the fulfilled gases is installed.

System of the operated ventilation of a case (PCV)

For elimination of leak of not burned down hydrocarbons in the atmosphere the engine is completely sealed. Gases and the oil evaporations which are formed in an engine case are passed via the mesh filter, go to the inlet pipeline and are burned in cylinders in the course of normal functioning of the engine

Removal of crankcase gases is carried out at the expense of a difference of pressure in a case and the inlet pipeline.

Catalytic converter

For decrease in number of harmful emissions in the atmosphere on all diesel models the catalytic converter is built in system of release. It neutralizes the most part of the gaseous hydrocarbons, monoxide of carbon (SO) and other toxic impurity which are contained in products of combustion of air-fuel mix.

System of recirculation of the fulfilled gases (EGR)

On all diesel models the system of recirculation of the fulfilled gases which main objective is decrease in percentage in products of combustion of the engine of nitrogen oxides (NOX) is also installed. For the purpose of performance of an objective a small part of the fulfilled gases from a path of system of release via the special valve is redirected the inlet pipeline (see also Undressed General information). Functioning of the EGR valve is controlled by the control unit.