Audi A4, S4

Since 2000 of release

Repair and car operation



Audi A4, S4
+ Introduction
+ Controls and receptions of safe operation
+ Current leaving and service
+ The engine
+ Systems of cooling, heating and the air conditioner
- Power supply systems, release and decrease in toxicity of the fulfilled gases
   + Power supply systems of petrol and diesel engines
   + System of injection of fuel of the petrol engine
   + System of injection of fuel of the diesel engine
   - Systems of release and decrease in toxicity of the fulfilled gases. turbocharger
      Removal and installation of system of release. Replacement of the central, additional muffler, a trailer pipe
      Updating of a lining of system of release / a trailer pipe
      Systems of decrease in toxicity of release - the general information
      The Katalitichesky converter
      Removal and installation каталитического the converter and ljambda-probes
      turbocharger - the general information and safety measures
      Интеркулер - the general information
+ Systems of an electric equipment of the engine
+ Manual box of a gear change
+ Automatic transmission
+ Coupling, power shafts and differential
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment



The Katalitichesky converter

The Katalitichesky converter has the central ceramic part of a cellular design-3 covered with a layer of the carrier. On a carrier layer there are the salts of precious metals operating as converters. The Katalitichesky converter is fixed in the case by-1 means изоляционного the basic layer-2 compensating simultaneously thermal expansions каталитического of the converter (address to an illustration the Arrangement of elements of system of injection in a compartment of the diesel engine 2.5).

Petrol engines

To reduce with the help каталитического the converter harmful emissions, injection systems should dose out precisely quantity of the injected fuel necessary for combustion. The Ljambda-probe is in a reception pipe before catalytic the converter and is washed by a stream of the fulfilled gases. The Ljambda-probe represents the electronic gauge measuring the maintenance of oxygen in final gases and representing its kind of fluctuations of pressure. The information from a ljambda-probe is transferred to the block of management of system of injection. The received value allows to regulate structure of an air-petrol mix. On the one hand it is necessary, as service conditions (the idling, full gas), on the other hand, constantly change as optimum reburning of fuel in каталитическом the converter occurs only in this case if in final gases fuel enough contains.

That in каталитическом the converter there was a fuel reburning, it is necessary to have temperature 300 - 800С. For this purpose it is necessary большее the fuel maintenance in a mix, than for pure burning.

The Katalitichesky converter of the petrol engine represents so-called трёхфункциональное the device. In adjustable process of transformation oxidation oxide carbon (WITH) and hydrocarbon (NANOSECOND), and also concentration reduction оксидов nitrogen (NOx) is carried out.

Security measures for an exception of damages каталитического the converter

For an exception of damages of a ljambda-probe and каталитического the converter it is necessary to fulfil following requirements:

Petrol engines

  • Necessarily apply only Unleaded gasoline.
  • Start of the heated-up petrol engine by pushing or towage is authorised to be spent only in one attempt and on distance no more the starting cable is better to apply than 50 m. to this purpose. Not burnt down fuel at ignition can lead to an overheat каталитического the converter and to its destruction.

Start of cars with АТ towage is impossible.

  • At difficulties with engine start it is not necessary to include a starter too long. Constant injection of fuel is thus made. It is necessary to reveal and eliminate a cause of defect.
  • If there are malfunctions with ignition system, at definition of their character it is necessary to exclude fuel injection at starter inclusion. For this purpose disconnect the relay of the fuel pump.
  • Never spend fuel in a petrol tank completely.
  • At occurrence of faults in ignition do not raise number of turns of the engine and immediately eliminate malfunction.
  • Apply only the recommended spark plugs.
  • Do not spend check of a spark with disconnected штекерным spark plug connection.
  • Carrying out of check of work of the cylinder by switching-off of a wire of ignition from its candle is not supposed. Thus not burnt down fuel gets in каталитический the converter.

Petrol and diesel engines

  • Do not stop the car over dry foliage or a grass. The system of release of the fulfilled gases in area каталитического the converter very hot also radiates heat even after an engine stop.
  • Do not put on elements of system of release of means for protection of the bottom of the car.
  • It is not supposed to change a design of heat-shielding screens.
  • At filling of the engine with oil especially pay attention to to exceeding at all the level designated on the index as Max. Surplus of oil owing to incomplete combustion arrives in каталитический the converter and can damage its covering from the alloyed metal or completely to destroy каталитический the converter.