Mercedes of the S-class W202

1993-2000 of release

Repair and operation of the car



Mercedes W202
+ 1.2. General information
+ 2. Maintenance
+ 3. Engines
+ 4. Lubrication system
+ 5. Cooling system
+ 6. Heating, ventilation
+ 7. System of ignition
- 8. Fuel system
   + 8.1.1. Introduction
   + 8.2. System of injection of petrol engines
   - 8.3. System of injection and power supply of diesel engines
      8.3.2. Check / control began fuel supply with the pump
      8.3.3. Nozzles
      8.3.4. Specifications of system of injection and power supply of the diesel
      8.3.5. Diagnostics of malfunctions of system of injection and food
   + 8.4. System of production of exhaust gases
+ 9. Transmission
+ 10. Running gear
+ 11. Steering
+ 12. Brake system
+ 13. Body
+ 14. Electric equipment
+ 14.2. Electrical circuitries






8.3. System of injection and power supply of diesel engines

8.3.1. Introduction

GENERAL INFORMATION

The scheme of system of injection with recirculation of exhaust gases

1. Fuel pump of high pressure
6. Clamp of the membrane mechanism of the vacuum regulator of an advancing of ignition
60. Valve of system of recirculation of exhaust gases
62b. A throttle with the filter
65. Valve of vacuum depression
67. Vacuum pump
99. Hydrovalve
100. Hydrovalve of the memebranny mechanism of the vacuum regulator of an advancing of ignition
105. Inlet gas pipeline
105a. Hydrovalve case
105b. The connecting pipeline of the let-in air
110. Final collector
128a. The thermostat (it is closed at 30 °C)
136. Flywheel
224. Accelerator pedal
B11/8. The dual thermal sensor (cooling the liquid / device предварительног a warming up)
L3. Rotation frequency sensor
N14. Relay of management
N22. Control device of the scheme of shutdown of the compressor of the refrigeration unit
N37. ARF monitor
S27/6. microswitch
Y27. The switching ARF valve
Y28. The switching hydrovalve gate

2,0 l engine: food of nozzles provides the line fuel pump of high pressure of Bosch with the mechanical regulator and the built-in antijog scheme of inclusion (KARA) which substantially reduces tortional fluctuations in a driving phase.

The actuation device of the antijog scheme of inclusion (N8/2) as well as the actuation device for recirculation of flue gases (AGR) is in a motor compartment behind a forward wall of a cabin under a casing for actuation devices on the right.

2,2 / 2,5 l engine: the electronic system of regulation of the diesel (EDC = electronic control of the diesel) promotes more exact coordination of injectable amount of fuel with the corresponding operating mode of the car thanks to what, in comparison with mechanical systems, considerable improvements almost on all operating modes are reached.

2,2 l engine: Mercedes for the first time puts into operation adjustable electronic system of injection of fuel with use of the distributive fuel pump of high pressure (EPIC = electronic programmable control of injection). Unlike the line fuel pump of high pressure which for each cylinder has a plunger couple the distributive fuel pump of high pressure is equipped only with two pistons of the pumping-up pump rotating in a rotor, and regulation of injectable amount of fuel, and also peak distribution (distribution of the beginning of peak loading at increase in frequency of rotation in the direction of "early injection") is carried out by means of the piston hydraulically operated by means of electromagnetic valves.

Valves are started by the electronic actuation device. The type and duration of the operating impulses depends on the factors registered by sensitive elements and processed in the actuation device by means of the sorted universal characteristics. Frequency of rotation of the engine, and also temperature of the let-in air, cooling liquid and fuel concern to them among others pressure in the inlet gas pipeline.

The provision of a pedal of an accelerator is defined by the setting device and the switch (R25/2) which signals are precisely entered into the electronic actuation device where they are processed and controlled. The setting device is located in a motor compartment behind a forward wall of a cabin at the left and connected with an accelerator pedal by means of a gas cable.

Operation of the engine stops by means of the electromagnetic valve. If its power supply itself is interrupted from the lock - the switch of ignition and devices of system of an anticreeper, or because of system mistakes in the operating electronics, then the valve blocks supply of fuel to pistons of the pumping-up pump. At malfunction of the disconnecting valve the actuation device installs system of amount of injectable fuel on "0" (zero giving) and, thanks to it, stops the engine. At the same time malfunction is remembered in the actuation device, and on the dashboard EDS - a control bulb flashes.

In addition with start of electromagnetic valves in the distributive pump of recirculation of flue gases (AGR) in combination with system of a drosselirovaniye of the let-in air (ALD) it is regulated by means of the engine management valve, and AGR - the valve and a butterfly valve are respectively put in action from pneumatic control point adjustments.

2,5 l engine: the 5-cylinder engine is also equipped with the system of injection of fuel regulated by means of electronics in combination with the line fuel pump of the high pressure (M/RE).

Instead of the mechanical regulator of frequency of rotation (the 2,0 l engine) the electromagnetic executive mechanism undertakes regulation by injectable amount of fuel according to the provision of a pedal of an accelerator. Definition of provision of a pedal of an accelerator is carried out by means of the control unit by the engine, as well as at the 2,2 l engine.

Along with regulation of amount of injectable fuel the electronic control unit power setting, besides, assumes regulation by recirculation of flue gases (AGR) in combination with a drosselirovaniye of the let-in air (ALD) depending on the frequency of rotation, loading and temperature of the engine.

The engine stops by means of the electrohydraulic switch (Y1/1) which is sideways on the fuel pump of high pressure. In the same case there is also a fuel thermal sensor (contacts 1/2).

The Toplivopodayushchy pump (13) is located outside of the line fuel pump of nozzles. The filter of rough cleaning is in the case of the main filter, and the warmed-up fuel follows from there thanks to what it, despite low external temperature, has the best fluidity.