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



turbocharger - the general information and safety measures

The general information

turbocharger. The diesel engine

turbocharger VTG

All diesel engines as well as some petrol engines, car AUDI A4 are equipped турбокомпрессором. On a shaft турбокомпрессора in two separate cases two driving wheels are located. The drive of turbine wheels is carried out from the fulfilled gases. They provide shaft rotation турбокомпрессора and by that both turbine wheels with a speed of 300 000 rpm. Greasing турбокомпрессора is carried out from system of greasing of the engine.

At the petrol engine турбокомпрессор it is in addition cooled by a liquid.

Owing to good filling of cylinders with forced air capacity of the engine increases to 100 %.

turbocharger it is intended for increase in capacity of the engine (to 100 %) by increase of pressure of air in the inlet pipeline. Air not simply arrives in cylinders, and moves in them under pressure. Along with capacity pressurisation creates increase in a twisting moment of the engine. Capacity growth, among other, depends on pressure of forced air which as a rule, makes 0.4-0.8 атм. Pressure of forced air is constantly supervised and regulated by the engine management block. It excludes possibility of excess of pressure over the established value. According to increase in giving of air, ТНВД increases fuel giving.

The compressor turbine is resulted in rotation by the fulfilled gases. Gases, passing through a special casing (a compressor casing), move to the compressor turbine. The turbine rotates on a shaft on which other end there is a compressor wheel in a separate casing. It submits air under pressure to the pipeline.

turbocharger with variable geometry of the turbine (VTG) has the directing shovels which position is regulated by the block of engine management by means of the electromagnetic valve and a vacuum drive. It provides optimum pressure of pressurisation in all range of turns that leads to higher twisting moment and, thereby, to higher capacity, in particular, at low numbers of turns.

Between турбокомпрессором and the inlet channel of the engine air cooler (интеркулер) which cools preliminary compressed турбокомпрессором air is located. It raises capacity of the engine since cold air thanking its higher density has higher maintenance of oxygen.

Pressure of air in the pipeline is limited to the special gauge. At achievement of limiting pressure the gauge opens заслонку, limiting to that giving of the fulfilled gases to the turbine.

The compressor shaft is greased with impellent oil which moves on specially intended hose. The shaft constantly "floats" in oil. From the compressor oil is taken away in the pallet on a returnable hose.

In comparison with the petrol engine the diesel engine does not have necessity to reduce degree of compression because of pressurisation that provides even on low turns full use of injected fuel.

turbocharger is a component of a final collector and cannot be separated from it.

turbocharger represents прецезионный the mechanism. Therefore at occurrence of malfunction it should be completely replaced.

Safety measures

Speed of rotation of turbines of the compressor is huge, and the working temperature is very great. To avoid reception of traumas, and also not to damage турбокомпрессор, observe following safety measures.

  • Do not start the engine after removal of any component турбокомпрессора. Hit of extraneous subjects on shovels of turbines can lead to an exit of the last out of operation. You also risk to be traumatised from the subjects thrown out from the turbine.
  • After removal any a component турбокомпрессора or air inlet hoses cover with its pure rags.
  • Do not give gas at once after engine start, especially if it is not heated-up. Oil cannot instantly grease a turbine shaft.
  • Never switch off ignition at once after a car stop. Do not press an accelerator pedal before an engine stop. At once after deenergizing of ignition oil ceases to move to a compressor shaft, and some time it will rotate without greasing.
  • Before muffling the engine, allow to it to work on single turns some minutes during which speed of rotation of the turbine considerably will decrease.
  • Regularly change oil, the oil filter and an air cleaner. Use of old oil will lead to formation of adjournment on a shaft of the compressor and to its exit out of operation. Before disconnecting hoses of giving and return of oil from the compressor, carefully clear nearby surfaces. The removed components store in tight containers.