Mercedes S-Class W-220

since 1998 release

Repair and operation of the car



Mercedes W220
+ Mercedes-Benz cars of the class S (W220)
+ Operation manual
+ Routine maintenance
+ Engine
+ Cooling system and heating
- Power supply system and release
   + Power supply system and fuel injection
   + System of injection of fuel of the diesel engine. Turbocompressor
   - Systems of release and decrease in toxicity of the fulfilled gases
      Systems of decrease in toxicity of release - the general information
      System of production of the fulfilled gases
      Catalytic converter
+ Engine electric equipment
+ Automatic transmission
+ Power shafts
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment
+ Schemes of electric equipment






Systems of release and decrease in toxicity of the fulfilled gases

Systems of decrease in toxicity of release - the general information

Elements of systems of decrease in toxicity

1 — the Control lamp "Check the engine"
2 — the Diagnostic socket

3 — the Valve of a purge of a coal adsorber


Scheme of laying of vacuum lines. V6 and V8 engines (112, 113)

1 — the adsorber purge Valve
2 — the Diaphragm device of switching of the inlet pipeline
3 — the Actuating unit of a butterfly valve
4 — the Resonant valve of switching of the inlet pipeline
5 — the Valve of a cut-off of admixture of air in an exhaust with the built-in control valve
6 — the Valve of system of recirculation of the fulfilled gases (EGR)

7 — the Vacuum transmitter of the EGR system
8 — To other consumers of depression
9 — the Vacuum control valve
10 — the Electric vacuum pump
11 — pressure Sensor
12 — the Valve of switching of the air pump


Arrangement of elements of systems of decrease in toxicity

1 — Right dokataliticheskiya a lambda probe 1
2 — Right post-catalytic a lambda probe 2
3 — pressure Sensor in the fuel tank
4 — the adsorber purge Valve

5 — the Adsorber of system of catching of vapors of fuel
6 — Left dokataliticheskiya a lambda probe 1
7 — Left post-catalytic a lambda probe 2


Function chart of system of catching of vapors of fuel

55 — the Fuel filter
55/2 — the Regulator of pressure of fuel of 5.0 atm.
55/3 — the Regulator of pressure of fuel of 5.3 atm.
55/3a — the Gate
55/4 — the spraying Camera
71 — the Valve
75 — the Fuel tank
76 — the Ventilating valve
77 — the Coal adsorber
77/1 — the Line of pressure/depression
95 — the mix pumping Pump

B4/7 — the fuel pressure Sensor
M3 — the Fuel pump
M3/1 — the Pump which is built in the fuel tank
N3/10 — the Control unit of electronics
the phased injection of fuel (ME-SFI)
Y58/1 — the Valve of management of an adsorber purge
a — the Fuel line
b — the Line of a purge
with — the Electrical wiring


The electric pump of system of admixture of air in an exhaust

The release switching gate valve (under the bottom)

The valve of switching of the pump of system of admixture of air in an exhaust (a forward part of the engine)

Valve of management of a purge of a coal adsorber (left back part of a motive compartment)

The transmitter of vacuum of the valve of recirculation of the fulfilled gases (a back part of the engine)


Petrol models

In power supply systems of all petrol models only unleaded gasoline has to be used. The control system of the engine functions so that to receive the maximum return from the engine at the minimum fuel consumption and toxicity of the fulfilled gases. The system of catching of vapors of fuel prevents hit them from the fuel tank in the atmosphere. The system of recirculation of the fulfilled gases is installed.

System of ventilation of a case

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).

Decrease in toxicity of the fulfilled gases

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 optimum concentration of oxygen in the fulfilled gases there is a jump in tension on the sensor. This jump is a reference point for the control unit at correction of quality of mix.

About two sensors are installed. One - before, and the second — after the converter. It reaches more exact tracking of composition of the fulfilled gases.

System of recirculation of the fulfilled gases

The system of recirculation of the fulfilled gases allows to reduce the number of NOx 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 vapors of fuel

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 valve of a purge (Y58/1) 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.

The control valve in the line of a purge prevents increase of pressure in an adsorber. The purge of an adsorber joins in the following cases:

- temperature of cooling liquid is more than 70 °C;
- the engine works longer than 2 min.;
- not at the movement by a setup;
- a lambda probe it is not active.

Regulation of force of a purge is carried out by the control unit. The size of replenishment of an adsorber is defined by various time of inclusion at constant opening and closing of the valve. Changes of speed of rotation of a bent shaft at a purge are prevented by management of single turns.

At an open cover of the fuel tank the ventilating valve does not open therefore the outlet is closed quicker and prevents hit of fuel in an adsorber.

Diesel models

The control system of the engine functions so that to receive the maximum return from the engine at the minimum fuel consumption and toxicity of the fulfilled gases. For additional decrease in toxicity of gases on the car several additional 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

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). On all diesel models the ventilation valve is installed. It is on a cover of a head of the block and operates a stream of gases from a case.

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 gaseous hydrocarbons, WITH and other harmful impurity which are a part of the fulfilled gases.

System of recirculation of the fulfilled gases

On all diesel models the system of recirculation of the fulfilled gases is also installed. This system allows to reduce the number of NOx 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 controlled by the control unit.