Audi S4

since 2000 release

Repair and operation of the car



Audi S4
+ Introduction
+ Governing bodies and methods of safe operation
+ Current leaving and service
+ Engine
- Cooling systems, heating and air conditioner
   - Cooling system
      General information
      Antifreeze - a security measure from freezing
      Replacement of cooling liquid
      Removal and installation of the thermostat
      Check of the thermostat
      Replacement of hoses of the cooling system
      Removal and installation of a radiator
      Removal and installation of the fan of a radiator
      Removal and installation of the pump of cooling liquid
   + Systems of ventilation, heating and air conditioning
+ Power supply systems, release and decrease in toxicity of the fulfilled gases
+ Systems of electric equipment of the engine
+ Manual box of gear shifting
+ Automatic transmission
+ Coupling, power shafts and differential
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment





Antifreeze - a security measure from freezing

Cooling liquid

The cooling system is all the year round filled with mix of water, antifreeze and rust-preventing agent. It interferes with a rust and corrosion, adjournment of salts and, besides, increases temperature of boiling of cooling liquid. In the cooling system because of expansion of liquid when heating excessive pressure is created that also leads to temperature increase of boiling of cooling liquid. Pressure is limited to the valve located in a cover of a broad tank which opens with a pressure of 1.4 - 2.0 atm. For faultless functioning of the cooling system it is required to be insured from boiling of cooling liquid at which the steam stopper therefore circulation of liquid decreases can be formed and cooling of the engine worsens. Temperature of boiling has to be increased. For this purpose the cooling system always has to be filled with mix of water and the listed additives to it.