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
      Operating procedure
      Malfunctions and independent diagnostics
      Independent repair
      Visual check
      Check of separate elements
      Check of the mode of idling and analysis of exhaust gases
      Check of catalytic converter and lambda probe
      Hummock drive of "gas"
      List of malfunctions
   + System of injection of Digifant
   + System of injection of KE-III-Jetronic
   + Systems of injection of MPI and MPFI
+ 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 separate elements

Check of the regulator of provision of a butterfly valve

The following paragraphs describe a procedure for test of components of system of injection which can be carried out in house conditions.

 PERFORMANCE ORDER

  1. To disconnect the plug of the regulator of provision of a butterfly valve.
  2. To bring the maximum voltage of 6 V to connecting contacts of a positioner; positive pole from above.
  3. At the 4-polar plug it is contacts 1 and 2 (both top).
  4. At the 6-polar plug it is contacts 1 and 6 (above and below).
  5. The necessary tension can be received from the 4,5-voltny battery or 6-voltny range of the charger.
  6. To replace a pole of a connecting wire (negative contact at the top contact pin).
  7. The pusher has to move forward completely.
  8. If everything occurs as is described, so the regulator of provision of a butterfly valve as it should be. If is not present, it needs to be replaced.
  9. In addition you can take measurements of resistance.
  10. Resistance of a winding of the auxiliary engine between already called connections of 3-200 Ohms.

Check of operation of the switch of a signal of idling

 PERFORMANCE ORDER

  1. To remove the plug from the regulator of provision of a butterfly valve.
  2. To connect an ohmmeter to contacts of the switch of a signal of idling.
  3. At the 4-polar plug it is contacts 3 and 4 (both lower).
  4. At the 6-polar plug it is contacts 4 and 5 (to look down).

 Help: after replacement of the regulator of a butterfly valve it is necessary to adjust the switch of a signal of idling is a work for a workshop.

Check of a potentiometer of a butterfly valve

On the block of preparation of gas mixture, in the direction on the car course, there is a regulator of provision of a butterfly valve (1) with the connecting plug (2).

At the left: check of a potentiometer of a butterfly valve: what indicators of resistance you have to receive on the potentiometer plugs designated here, you can see in the table.

 Contacts
Check conditions
Resistance, Ohm
Mechanical transmission
Automatic transmission

1 + 5

1 + 7

520 – 1300

1 + 2

1 + 2

From the situation "the butterfly valve is closed" to "it is open approximately on 1/4": resistance increases, then becomes constant
600 – 3500

1 + 4

1 + 6

From the situation "the butterfly valve is closed" to "it is open approximately on 1/4": resistance constant, increases then
600 – 6600

On the right: check of a vpryskny nozzle and the sensor of temperature of the arriving air. On an illustration the arrangement of connections of the general plug is shown.


 PERFORMANCE ORDER

  1. To disconnect the plug of a potentiometer of a butterfly valve.
  2. To connect an ohmmeter according to the table to two of four plug contacts.
  3. If the specified sizes are not reached, so the potentiometer of a butterfly valve is faulty. Unfortunately, it is impossible to replace only it. All lower part of the block of preparation of gas mixture changes always.

Check of a vpryskny nozzle

 PERFORMANCE ORDER

  1. Check at the working engine: temperature of oil has to make at least 60 °C that corresponds 10 min. the movement after start of the cold engine.
  2. To remove an air inlet branch pipe.
  3. To start the engine, to leave to work at single turns.
  4. To watch a stream of injectable fuel. It has to be uniform and directed on a butterfly valve.
  5. To kill the engine to check tightness of the valve.
  6. At the switched-off engine no more than two drops in a minute have to act.
  7. You will need to carry out further inspections if the engine is not started.
  8. To check safety locks 13 and 27.
  9. To remove the air filter and a branch pipe of an air inlet.
  10. The assistant has to turn the engine a starter.
  11. The Vpryskny nozzle has to inject fuel considerably.
  12. If it does not occur, to disconnect the brown plug above on the block of preparation of gas mixture.
  13. To connect an ohmmeter to both average connecting contacts (on the block of preparation of gas mixture).
  14. At ambient temperature between +15 and +30 °C the ohmmeter has to show 1,2 — 1,6 Ohms, otherwise the nozzle is faulty. To unscrew the screw with a star-shaped head and to replace a nozzle.
  15. To check power supply of a vpryskny nozzle if it does not work despite right indicators of resistance.
  16. To connect the LED voltmeter, without using other device, to both average contacts in the removed plug.
  17. To include a starter: light-emitting diodes have to flicker, otherwise there is a break of conducting or malfunction of the control unit.

Check of interruption in supply of fuel in the mode of compulsory idling (at the movement by a setup)

 PERFORMANCE ORDER

  1. To remove the air filter or a branch pipe of an air inlet.
  2. To start the engine, quickly to bring rotation frequency to 3000 rpm, and then sharply to close a butterfly valve.
  3. Well visible vpryskny stream of a vpryskny nozzle has to in this the moment for a short time stop. In this case interruption in supply of fuel in the mode of compulsory idling as it should be.
  4. If is not present, to check the sensor of angular movement of a butterfly valve and the control unit (in a workshop).

Check of sensors of temperature

On this chart you see indicators of the sensor of temperature of the arriving air near a vpryskny nozzle and also the sensor of temperature of cooling liquid in a branch pipe at the engine at the left. The illustration shows sensor resistance size depending on temperature.


 PERFORMANCE ORDER

  1. The sensor of temperature of the arriving air: to disconnect the brown plug from above on the block of preparation of gas mixture.
  2. To connect an ohmmeter to both external plug contacts.
  3. Sensor of temperature of cooling liquid: to disconnect the plug on the sensor (blue) in a bulk branch pipe of cooling liquid.
  4. To connect an ohmmeter to plug contacts of the sensor.
  5. Both sensors: to remove resistance indicators.
  6. According to the chart you can check, whether there are indicators of resistance of sensors, and also air temperature and okhladayushchy liquid at the time of measurement within admissible range.
  7. If this is so, so sensors as it should be.

Check of pressure of supply of fuel

 PERFORMANCE ORDER

  1. Pressure of supply of fuel can be precisely checked only by the measuring device used in a workshop.
  2. At suspicion on the incorrect pressure of supply of fuel to disassemble pressure regulator: to turn off 4 bolts with a star-shaped head.
  3. To check, whether the membrane is damaged and whether there are no the polluting deposits.