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
- Systems of an electric equipment of the engine
   + Ignition and engine management system
   - System of preheat of the diesel engine
      The general data
      Removal and installation of candles накаливания
      Check of candles накаливания
   + Diagnostics of systems of electronic control and the diagnostic equipment
   + Gymnastics and start systems
+ Manual box of a gear change
+ Automatic transmission
+ Coupling, power shafts and differential
+ Brake system
+ Suspension bracket and steering
+ Body
+ Onboard electric equipment


System of preheat of the diesel engine

The general data

On the cold diesel engine, at air compression in the cylinders, necessary for spontaneous ignition of fuel the temperature is not reached. For this reason preheat is required.

With that end in view in each chamber of combustion the candle накаливания is established. The candle накаливания consists of the case with впрессованным in it a heating core. The heating core in turn consists of a heating spiral and an adjusting spiral. After pressure giving the heating spiral in a core heats up within several seconds to temperature + 850°С. Thus the current which is passing on a candle, reaches 30А. At heating increase resistance increases filched that limits a current to 15 - 25 A.Kogda a control lamp of preheat on the panel of devices die away, the engine can be started.

Time of preheat necessary for start of the engine, makes no more than 10 with. Time is regulated the relay of preheat and the block of engine management which through the gauge of temperature of a cooling liquid receives the information on current temperature of the engine. The block of engine management on the basis of the received information makes the decision on duration of inclusion of candles накаливания and a necessary current of heating.

On the diesel engine with direct injection preheat is required only at temperature more low 0°С.


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