S-class W202 Mercedes

1993-2000 of release

Repair and car operation

W202 Mercedes
+ 1.2. General information
+ 2. Maintenance
+ 3. Engines
+ 4. Greasing system
+ 5. Cooling system
+ 6. Heating, ventilation
- 7. Ignition system
   7.2. Safety measures at repair of electronic system of ignition
   7.3. Ignition coils
   + 7.4. Spark plugs
   + 7.5. Device of a preliminary warming up of a diesel engine
+ 8. Fuel system
+ 9. Transmission
+ 10. Running gear
+ 11. Steering
+ 12. Brake system
+ 13. Body
+ 14. Electric equipment
+ 14.2. Electroschemes

b47c026d ac- 700-WWVB.
b47c026d ac- 700-WWVB.

7. Ignition system

7.1. Introduction


The system of ignition develops sparks which ignite the gas mixture which is let in cylinders of an internal combustion engine. To develop a powerful igniting spark, in ignition coils tension of the storage battery will be transformed from 12 Volts approximately to 30000 Volts.

Petrol engines of the S-class have the statistical distributor of ignition of a high voltage, so-called direct ignition. In such system of ignition there are no moving details and the traditional distributor of ignition equipped with a begunok. Thanks to it there is no more wear of these details and operational reliability raises.

Actuating of igniting sparks by means of coils of ignition is carried out directly by means of the regulating device of the engine which also operates system of injection of gasoline. At the 4-cylinder engine of the coil of ignition are established on the block of cylinders of the engine, and at the 6-cylinder engine – under a casing of wires of a high voltage of a cover of a head of the block of cylinders. Each two cylinders receive the igniting sparks from one general coil of ignition. Thus one ignites gas mixture in a step of its admission in the corresponding cylinder. For starting reliability at start-up of the cold engine some igniting sparks on one working piston stroke (so-called multispark ignition) are developed.

1. Corner of an advancing of ignition
2. Loading
3. Frequency of rotation

The regulating device which is based on the characteristic of ignition is applied to definition of the correct moment of ignition, saved up in memory by means of electronics. Thanks to it it is possible to coordinate easier rather among themselves various service conditions, for example, other quality of fuel.

The system of anti-detonation regulation at engines, since working volume of cylinders in 2,2 l, promotes operation of cars with a high compression and smoothes application of fuel of various quality. At the 4-cylinder engine on the block of cylinders of the engine one is established, and at the 6-cylinder engine two sensors of detonation combustion. They regulate detonation combustion in the engine and make on it impact by means of the corresponding impulses arriving from the regulating device of the engine, changing the ignition moment towards the late. Thanks to it the detonation of the engine and emergence of malfunctions in it is prevented.

If in engines in volume of 1,8/2,0 l gasoline of poor quality is mainly used only, by means of the soglasuyushchy tip in a motor compartment ignition should be switched to other characteristic.

At repairs of electronic system of ignition it is necessary to observe safety regulations to avoid a travmirovaniye of the persons who are engaged in these works, or damage of system of ignition.