Mercedes S-Class W-140

1991-1999 of release

Repair and operation of the car



Mercedes S-Class
+ Mercedes-Benz cars of the class S (W-140)
+ Operation manual
+ Routine maintenance
+ Engine
+ Cooling systems, heating
- Power supply system and release
   + A power supply system and injection of fuel of the petrol engine - the general information
   + System of injection of fuel of the diesel engine - the general information
   + Control system of injection of fuel and HFM-SFI ignition (6-cylinder petrol engines)
   + Control systems of the LH-SFI and ME-SFI engine (8-cylinder petrol engines)
   + Control systems of injection of fuel and ignition of ME-SFI and LH-SFI (12-cylinder petrol engines)
   + Control system of fuel injection (diesel engines of the OM603.971 series)
   + Control system of fuel injection (diesel engines of the OM606.961 series)
   + System of a turbo-supercharging - the general information
   Systems of decrease in toxicity of release - the general information
   System of production of the fulfilled gases - the general information
   Catalytic converter (petrol models)
+ Engine electric equipment
+ Gear shifting box
+ Automatic transmission
+ Coupling
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment






Systems of decrease in toxicity of release - the general information

General information

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.

Function charts of systems of decrease in toxicity of the fulfilled gases (as parts of a control system of the engine)

The function chart of system of injection of vdigatel 119 and 104 (the engine 119 is shown)


40 — the Diaphragm regulator of pressure
55 — the Fuel filter
60 — the Vacuum device
74 — a fuel Cooler
75 — the Fuel tank
76 — the Ventilating valve
77 — the Coal adsorber of vapors of gasoline
89 — the EGR Valve (left on the engine 120)
89a — the Right EGR valve on the engine 120
98 — the Damping pneumatic device of switching to the raising transfer
125 — the Air pump
126 — the Valve of a cut-off of admixture of air in a final collector
127 — the Backpressure valve of admixture of air in a final collector (left on the engine 120)
127a — the Backpressure valve of admixture of air in right, on the engine 120, a final collector
128 — the Backpressure valve (depression)
135 — the Backpressure valve (depression creation)
136 — the Vacuum chamber
156 — the Final collector
158 — the Catalytic converter
A1e26 — the Control lamp of refusals (MIL/" Check the engine")
A9 — the K/V Compressor
A16 — Sensors of a detonation (KS)
A16g1 — the Left sensor of a detonation of KS
A16g2 — the Right sensor of a detonation of KS
B2/2, B2/3 — the Thermometric sensor of measurement of mass of air (MAF)
B11/2 — the 4-contact sensor of temperature of cooling liquid (ECT)
B11/7 — the Sensor of temperature of the soaked-up air (IAT)
B11/9 — the Left ECT sensor
B17/5 — the Left IAT sensor on the engine 120
B17/6 — the Right IAT sensor on the engine 120
B17/7 — the Sensor of temperature of the soaked-up air (IAT)

G3/2 — Warmed up a lambda probe (left on the engine 120)
G3/4 — Right warmed up a lambda probe on the engine 120
K17 — the Relay of system of admixture of air in a final collector
K27 — the Relay of the fuel pump
K27/1 — the Left relay of fuel pumps 1 and 2 on the engine 120
K27/2 — the Right relay of fuel pumps 1 and 2 on the engine 120
L5 — the Sensor of provision of a bent shaft (CKP)
L5/1 — the Sensor of position of the camshaft (CMP)
L5/2 — the Left CMP sensor on the engine 120
L5/3 — the Right CMP sensor on the engine 120
L5/4 — the Left CKP sensor on the engine 120
L5/5 — the Right CKP sensor on the engine 120
M3m1 — the Fuel pump 1
M3m2 — the Fuel pump 2
M16/1 — the Actuation mechanism of acceleration (the drive of a butterfly valve)
M16/3 — the Left drive of a butterfly valve on the engine 120
M16/4 — the Right drive of a butterfly valve on the engine 120
N1/3 — the Control unit of system of ignition EZL/AKR
N1/4 — the Left control unit of system of ignition on the engine 120
N1/5 — the Right control unit of system of ignition on the engine 120
N3/1 — ECM
N3/2 — the Left ECM on the engine 120
N3/3 — the Right ECM on the engine 120
N4/1 — the Control unit of acceleration (the drive of a butterfly valve)
N4/3 — the Control unit of system of stabilization of turns of idling (IAC)/tempostata
N16/1 — the Voltage stabilizer
N59 — the Diagnostic module (the Californian models)


Funktsonalny scheme of system of injection of the engine 120

R16/2 — the Model resistor of the module of ignition
R16/3 — the Model resistor of the left module of ignition on the engine 120
R16/4 — the Model resistor of the right module of ignition on the engine 120
S29/3 — the Trailer sensor switch of idling
S40 — the Switch of a tempostat
A — Vykl
B — Dispersal/installation
SP — Reinstallation
V \Braking engine/installation
S65 — the Safety switch of an overload of transmission (a tape brake of B1)
S65/1 — the Safety switch of an overload of transmission (a tape brake of B21). Engine 120
T1 — the ignition Coil
T1/1 — the Coil of ignition of the right head of cylinders on the engine 120
T1/2 — the Coil of ignition of the left head of cylinders on the engine 120
Y3/3 — the Pneumatic valve of a damper of switching to the raising transfer
Y27 — the Switching EGR valve

Y27/2 — the Left EGR switch on the engine 120
Y27/3 — the Right EGR switch on the engine 120
Y32 — the Switching valve of the pump of admixture of air in a final collector
Y33 — the Electromagnetic coupling of the pump of admixture of air in a final collector
Y49 — the Electromagnetic valve of the regulator of the camshaft
Y49/1 — the Electromagnetic valve of the regulator of the camshaft of the left head of cylinders on the engine 120
Y49/2 — the Electromagnetic valve of the regulator of the camshaft of the right head of cylinders on the engine 120
Y58/1 — Pnevmopereklyuchatel of a coal adsorber
Y58/2 — the Left pneumoswitch of a coal adsorber on the engine 120
Y58/3 — the Right pneumoswitch of a coal adsorber on the engine 120
Y62 — Fuel injectors (the left number of cylinders on the engine 120)
Y63 — Fuel injectors of the right number of cylinders on the engine 120


Scheme of laying of vacuum lines (engines 104)

1 — the Vacuum receiver
2 — the depression Distributor
3 — the Resonant gate
4 — the air cut-off Valve (with the built-in control valve)
5 — the Electric vacuum pump
6 — the Valve switch of the air pump
7 — the Vacuum control valve

8 — the Diaphragm regulator of pressure
9 — the Sensor of absolute pressure in the inlet pipeline (MAP)
10 — the Valve of management of a purge
11 — To a coal adsorber
12 — the Activator of a butterfly valve


Scheme of laying of vacuum lines (engines 119)

1 — the Vacuum receiver
2 — the Control valve of giving of depression
3 — the Diaphragm regulator of pressure
4 — the Valve of management of a purge
5 — To the module of management of system of injection ME-SFI

6 — To a coal adsorber
7 — the Electric air pump
8 — the air supply shutdown Valve
9 — the Sensor of absolute pressure in the inlet pipeline (MAP)
10 — the Valve switch of the air pump


The scheme of an eyeliner of vacuum and vaporizing lines to the inlet pipeline (engines 120)

40 — the Diaphragm regulator of pressure
125 — the Air pump
126 — the air cut-off Valve
126a — the Right valve of a cut-off of air
127 — the Left control valve (air admixture)
128 — the Vacuum control valve
135 — the Control valve of the line of giving of depression
136 — the Vacuum receiver
M16/3 — the Left activator of an electronic accelerator /
темпостата / control units turns
idling. In the left part of the power unit

M16/4 — the Right activator of an electronic accelerator /
темпостата / control units turns
idling. In the right part of the power unit
Y32 — the Valve switch of the air pump
Y33 — the Electromagnetic clutch coupling air
pump
Y58/2 — the Left valve of management of a purge
Y58/3 — the Right valve of management of a purge
a — to a coal adsorber
rt — red
gr — gray
sw — black
tr — neutral

The injector of the first cylinder is in the right forward part of the power unit (on the example of the 12-cylinder engine)

Assembly of the fuel pump is located under the car, ahead of the right back half shaft

The relay of the fuel pump is on the right in the luggage compartment, behind the back assembly block of safety locks

The sensor of a reserve of fuel is in the left forward corner of the luggage compartment, on the fuel tank

The valve of switching of the inlet pipeline is located under the inlet pipeline (bottom view)

The left thermometric measuring instrument of mass of air (MAF) is located in the right part of a motive compartment, on an air inlet sleeve

The left sensor of temperature of cooling liquid is located at the left in a forward part of the power unit

The right sensor of temperature of cooling liquid is located at the left in a forward part of the power unit

The sensor of temperature of cooling liquid (ECT) is in the top part of the left forward corner of the power unit

The left sensor of a detonation (KS) is in deepening from above on the engine (in a picture the engine is removed from the car)

The left sensor of a detonation (KS) 1 is in deepening from above on the engine (in a picture the engine is removed from the car)

The right sensor of position of the crankshaft (CKP) on dvigatelev12, - behind in the top part of the block of cylinders (the engine is removed from the car)

The left sensor of position of the crankshaft of a bent shaft (CKP) on the V12 engine, - on the right on a back wall of the block of the engine (in a picture the engine is removed from the car)

Left dokataliticheskiya a lambda probe 1, - under the car, closely to DP, over the catalytic converter

Dokatalitichesky a lambda probe 1, - under the car, closely to DP, on tubular section of system of release, in front of the catalytic converter

Left post-catalytic a lambda probe 2, - under the car, near DP

Post-catalytic a lambda probe 2, - under the car, near DP under a back seat, in a pipe of system of release behind the catalytic converter

The electromagnetic coupling of the pump of admixture of air is from below in the right forward corner of a motive compartment

The right valve of a purge of an adsorber is located in the left part of a motive compartment, on a mudguard of a wheel arch

The left valve of a purge of an adsorber is located in the right part of a motive compartment, on a mudguard of a wheel arch, behind a broad tank of the cooling system

The valve of a purge of an adsorber is in the left forward corner of a motive compartment, on a mudguard of a wheel arch

The valve of a cut-off of a purge of an adsorber is located under the car, in a back part of an arch of the left back wheel

System of 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).

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.

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.

System of recirculation of the fulfilled gases (EGR)

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 (EVAP)

Address schemes of a control system of the engine (A control system of the engine of models of 3.2 l, the Control system of the engine of models 4.2 and 5.0 of l).

For decrease in emission in the atmosphere of not burned down hydrocarbons on all petrol models the system of catching of vapors 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.

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 continuous 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). 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.