Audi A4, S4

since 2000 release

Repair and operation of the car



Audi A4, S4
+ Introduction
+ Governing bodies and methods of safe operation
+ Current leaving and service
+ Engine
+ Cooling systems, heating and 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
      General information and security measures
      Functioning of a control system and injection of the petrol engine
      General check of system of injection of the petrol engine
      Check and adjustment of number of turns of the single course / moment of ignition/concentration WITH
   + System of injection of fuel of the diesel engine
   + Systems of release and decrease in toxicity of the fulfilled gases. Turbocompressor
+ 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






System of injection of fuel of the petrol engine

General information and security measures

The system of electronic control by operation of the engine regulates process of distribution of fuel and process of ignition of fuel mix. The electronic control system allows:

  • Precisely to dose amount of injectable fuel in any operating mode of the engine that provides low fuel consumption at optimum road performance of the car.
  • To reduce the content of harmful substances in the fulfilled gases owing to exact measurement of amount of fuel and use of the adjustable catalytic converter.
  • To carry out self-diagnostics for fast troubleshooting. The system is equipped with memory of malfunctions. If in the course of work there are malfunctions, they register in memory. If the engine works not optimum, the list of malfunctions can print HUNDRED if necessary to eliminate damage independently.

The control unit of the engine represents the small, high-speed computer. He determines optimum time of ignition, the moment of injection of fuel and amount of injectable fuel. Thus there is a coordination of operation of the control unit with other systems of the car, for example, by management of a transmission or blocking from stealing.

Elements of system of ignition and injection keep the working capacity for a long time and practically do not demand service. Within carrying out maintenance it is only necessary to make replacement of an element of the air filter, and also to replace spark plugs. More serious works on control and repair can be made only by means of special devices.

Security measures during the work with system of injection of the petrol engine

  • Do not use naked flame, do not smoke, do not hold near a workplace of any heated or very hot details. There is a danger of accident! Keep in readiness the fire extinguisher.
  • Watch good ventilation of a workplace. Fuel couples are poisonous.
  • The fuel system is under pressure! Before dismantling of hose connections dump fuel pressure, address to the Section Dropping Pressure in fuel system.
  • When dismantling hose connections for safety reasons connection needs to be covered with a thick rag.

During the work with elements of system of injection it is also necessary to follow the general safety rules and purity observance described in the Section General information and security measures.

Elements of a control system of the engine keep the working capacity for a long time and practically do not demand service. Within carrying out maintenance it is necessary to replace only an element of the air filter and the fuel filter.