Audi A4

since 1994 release

Repair and operation of the car



A4 Audi
+ Running gear
+ Regular servicing
+ Engines
+ Turbo-supercharging
+ System of an exhaust
+ Cooling system
+ Fuel tank and fuel pump
+ Air filter and channels of absorption
+ System of injection
+ Coupling
+ Transmission and main transfer
+ Suspension bracket of wheels and steering
+ Brakes
+ Wheels and tires
+ Electrotechnical equipment
- System of ignition
   That provides ignition
   When there is an ignition of fuel and air mix?
   Different systems of ignition
   So there is an ignition spark
   Executive body
   Brain of system
   The signals coming to the control unit
   Adjustment of a detonation
   Be careful in the address with ignition
   Works on system of ignition
   Search of malfunctions in ignition
   Ignition distributor
   Knot of a high voltage
   Replacement of spark plugs
   Right choice of spark plugs
   Check of the moment of ignition
+ Lighting
+ Alarm equipment
+ Tools and devices
+ Heating and ventilation
+ body Details
+ Salon
Search of malfunctions
Technical characteristics





Brain of system

Control unit

Management of ignition and injection is joint in one electronic block. In the same place installation of the moment of ignition pays off.

  • All possible data and characteristics of the engine are at the disposal of the control unit. It is provided by the sensor of the Hall or the sensor of number of turns of the engine and position of the crankshaft, and also sensors of temperature of the engine, the provision of a butterfly valve, etc.
  • If to express an ignition corner (the ignition moment) by means of a condition of load of the engine and numbers of turns of the engine, we will receive the so-called characteristic of ignition. The characteristic of ignition of Motronic is willingly shown because of the unusual form – she allows to draw a conclusion on exact influence of these parameters on a working condition of the engine.
  • Certainly, there is a data exchange to injection. Including because at some sensors on the engine a dual purpose.
  • Programs of correction of start of the engine, operation of the cold engine, operating mode and so forth are at the disposal of the control unit.
  • The control unit gives such current what it needs at present on ignition coils. In an extreme case (ignition is included, the engine does not work) at such ignition it cannot lead to damage of the coil even through long time.
  • Adjustment of a detonation allows to operate the engine with the greatest possible advancing of ignition that the best gives vent to power.
  • Therefore the engines with power up to 110 kW designed for operation on superfuel at some loss of power can work also at standard gasoline since the control unit distinguishes lower octane number and switches to other characteristic of ignition.
  • On the other hand, with the 128 kW engine the best draft by use of gasoline super plus with octane number 98 is reached. In this case standard gasoline is provided only as the compelled decision at the extremely sparing style of the movement.
  • And, at last, the computer for saving of information on malfunctions in system of ignition which is read out in a workshop by means of the device for reading is still installed (the head Regular servicing).