Audi 80/Avant (B4)

since 1991-1995 release

Repair and operation of the car

Audi 80/Avant
+ Technical specification
+ Engines
+ System of production of the fulfilled gases
+ Cooling system
+ Fuel tank and fuel pump
+ Air filter and airintaking channels
- System of injection
   + System of injection of Mono-Motronic
   + System of injection of Digifant
   + System of injection of KE-III-Jetronic
   - Systems of injection of MPI and MPFI
      Operating procedure
      Lambda regulation
      Malfunctions and independent diagnostics
      Independent repair
      Visual check
      Check of separate elements
      Removal of elements
      Hummock drive of "gas"
      Check of the mode of idling and analysis of exhaust gases
      List of malfunctions
+ Coupling
+ Transmission and transmission
+ Suspension bracket and steering
+ Brake system
+ Anti-blocking system of brakes
+ Wheels and tires
+ Body electrical system
+ System of ignition
+ Lighting
+ Signalling devices
+ Devices and auxiliary devices
+ Heating and ventilation
+ body Elements
+ Search of malfunctions
+ Specifications

Check of the mode of idling and analysis of exhaust gases

6-cylinder engines are supplied with automatic control of frequency of rotation of a shaft of the engine in the idling mode.

The adjusting bolt is absent – so even there is nothing to regulate. Rotation frequency in the idling mode simply is checked. In the correct conditions of check (about it below) the following indicator of frequency of rotation of 680 - 820 rpm (the 2,6-liter engine) or 700 – 800 rpm (the 2,8-liter engine) has to be established. Otherwise:


  1. To check all elements of inlet system (the pipeline, sealing laying) for tightness. The getting unaccounted air can change so strongly rotation frequency in the idling mode that the distributive valve of stabilization of idling will not be able to compensate it even.
  2. To interrogate memory of the store of malfunctions in a workshop. Perhaps, in system there is other malfunction.

Check conditions


  1. Conditions of check of frequency of rotation in the mode of idling are temperature of the engine warmed up to the working temperature, and also serviceable systems of injection and ignition.
  2. Further it is necessary to disconnect in the car everything consumers of electricity.
  3. The cooling system fan also should not work.
  4. To remove both ventilating pipelines of a case, to muffle the ends of hoses.
  5. To switch off the conditioner.
  6. To install the handle of switching of an automatic transmission in the situation "N" or "P".
  7. To warm up the engine (temperature of oil of at least 60 °C) up to the working temperature.
  8. The replaceable element of the air filter has to be in faultlessly pure state.
  9. For the analysis WITH the exhaust device should not be connected to system of release.

The analysis of the fulfilled gases

In house conditions an inspection of the contents WITH usually is not carried out as this procedure is obligatory when passing annual checkup. Besides, the special device is for this purpose necessary.

It is checked only after system of injection by means of the device of reading of the store of malfunctions of V. A. G. 1551 it will be provided to a so-called basic position. That means shutdown of certain adjusting functions (for example, a lambda regulation) for obtaining reasonable comparable sizes.


  1. To connect the device for measurement of toxicity of the fulfilled gases to the right measuring tube ahead in a motor compartment. To watch a dense prileganiye.
  2. To start the engine and to leave to work at single turns.
  3. The measuring device has to show 0,15 – 1,0% of CO (the 2,6-liter engine) or 0,3 – 1,2% WITH (the 2,8-liter engine).
  4. At models with the 2,8-liter engine the contents WITH can be adjusted by means of the adjusting screw at an air flowmeter.
  5. At models with 2,6-liter the engine possibility of regulation is absent. If measurement showed other contents WITH, it is necessary to look for the reason by means of the store of malfunctions.

The indicator WITH differs from the standard

Generally at different indicators WITH it is necessary to look for not tight places in system of air supply and production of exhaust gases. Further it is necessary to establish that as it should be system of ignition (the faulty spark plug raises the contents WITH for 1,5%).

Too high rate WITH:

  • To check vpryskny nozzles.
  • Too high pressure of fuel.
  • The sensor of temperature of cooling liquid is faulty.

Too low indicator WITH:

  • Unaccounted air gets to system of air supply.

 Help: everything that you have to know about the test for the contents WITH, check of effect of catalytic converter, check a lambda probe and the hummock drive of "gas", you will find in the head "System of injection of Mono-Motronic".

Shutdown of the battery erases correction coefficient of frequency of rotation of a shaft of the engine in the mode of idling of system of injection. Therefore the system has to approach anew slowly the correct indicator of frequency of rotation, and this process lasts some minutes. So do not panic at once if after replacement of the battery the car suddenly works not absolutely faultlessly, it is necessary to pass simply a little, regulation will not come to the end yet.