Audi 80/Avant (B4)

Since 1991-1995 of release

Repair and car operation

Audi 80/Avant
+ The description
+ Engines
+ System of release of the fulfilled gases
+ Cooling system
+ Fuel tank and the fuel pump
+ The air filter and воздухозаборные channels
- Injection system
   + System of injection Mono-Motronic
   + System of injection Digifant
   - System of injection KE-III-Jetronic
      Basic elements
      Operating procedure
      Malfunctions and independent diagnostics
      Independent repair
      Visual check
      Check of separate elements
      Search of malfunctions
      Removal of components
      Check of a mode of idling and the analysis of exhaust gases
      The list of malfunctions
   + Systems of injection MPI and MPFI
+ Coupling
+ Transmission and transmission
+ Suspension bracket and steering
+ Brake system
+ Antiblocking system of brakes
+ Wheels and tyres
+ Kuzovnaja electrosystem
+ Ignition system
+ Illumination
+ Signalling devices
+ Devices and auxiliary devices
+ Heating and ventilation
+ Body elements
+ Search of malfunctions
+ Specifications

Search of malfunctions

The 5-cylinder engine: the starting fuel valve (2) with the tip (1).

On an illustration on the right you see the proof-reader of structure of a gas mixture with запорным the valve (1), an air nozzle (2), the air filter (3), дозатором (4), a regulator of pressure (5) and a potentiometer запорного the valve (6).

Drawing at the left shows correct position запорного the valve with an air nozzle. It should be exactly on and = 1,9 mm below an upper edge of a narrow cylindrical part of an air nozzle. If necessary to correct by easy bending of a spring (presented on drawing in the form of "snake"). Attention: flowmeters of air of newer type are supplied by an adjusting bolt instead of a spring. In this case position запорного the valve юстируется the mentioned bolt.

The distributive valve of stabilisation of idling of the 5-cylinder engine is located on the right in front at a head of the block of cylinders.

At the removed sleeve of an air inlet in the case of throttle knot both are visible throttle заслонки (3 and 4). Above on the case there is a system drivers draughts (2) which opens at first one, and by the further pressing an accelerator pedal the second throttle заслонку. The position (1) displays the switch of a signal of idling.

On a head of the block of cylinders in front at the left in a branch pipe of system of cooling are: the gauge of temperature of the engine of system of injection (1), and also an electronic thermoswitch (2) indicators of temperature of a cooling liquid, a control bulb of a cooling liquid, the conditioner, etc.

The diagramme below shows size of resistance of the gauge of temperature of a cooling liquid depending on temperature.

In following sections we have considered those possibilities of search of malfunctions for which in house conditions no especial tools or measuring devices are necessary. If you after perusal of our list of malfunctions (in the end of the head) or after reading of memory of the store of malfunctions have suspected a certain detail here you will find the control scheme.

Check впрыскных atomizers


  1. To disconnect ignition system under the scheme described in the head System of ignition.
  2. To check up, whether gasoline, ослабьте bolts on bringing топливопроводе arrives in system of injection.
  3. Do not forget about a rag because in most cases from топливопровода gasoline will scatter. Otherwise ask the assistant to work as a starter.
  4. If fuel arrives, means, supply is perfectly in order – hence, in the second turn it is necessary to check atomizers.
  5. To remove an atomizer, the description see more low in this chapter. For this purpose the top part of an inlet collector at first should be removed.
  6. To keep in readiness capacity or a rag for fuel gathering.
  7. To remove the big air line between the proof-reader of structure of a gas mixture and the case of throttle knot for access reception to запорному to the valve.
  8. To remove in the central switching centre of the relay of the fuel pump on штекерной to a cell 10 (the Fuel tank and the fuel pump see the head).
  9. On a cell 10 to connect штекерные contacts 48 (or 30) and 52 (or 87) a wire slice. The fuel pump should earn.
  10. A few to raise a hand запорный the distributor valve. Now the atomizer should is cone-shaped to inject gasoline. Otherwise:
  11. To lift запорный the valve once against the stop. To repeat check.
  12. In the same way it is possible to check up a difference in number of injected fuel between separate cylinders. However this way suits only for want of something better.
  13. To direct all five atomizers to five measuring capacities, thus not to bend hoses топливопровода.
  14. A few to raise (approximately on 2 sm) запорный the valve.
  15. The assistant should support the mentioned crosspiece until in the first capacity 20 sm3 (ml) of fuel will not gather.
  16. To compare quantity of injected fuel. The difference should not make more than 2,5 sm3.
  17. In case of the big deviations to change places of an atomizer with the greatest and the least indicators. To repeat measurement.
  18. If deviations "have moved" together with atomizers, means, has come to replace time atomizers with corresponding deviations.
  19. If you have received former results of measurements on cylinders with deviations it is not excluded that is made narrower топливопровод to an atomizer or is faulty дозатор.
  20. Check of tightness of atomizers: if to disconnect the fuel pump after two-minute work with raised запорным the valve (to remove a crosspiece) fuel from atomizers should not to act.

Check of the starting fuel valve


  1. To disconnect ignition system under the scheme described in the head System of ignition.
  2. To remove the starting fuel valve, to remove a wire tip, to leave connected a tube топливопровода.
  3. A few to work as a starter that the fuel pump could create pressure.
  4. To lower an atomizer in capacity, to connect two auxiliary wires to valve contacts.
  5. To connect the free ends of wires to accumulator conclusions – one with +, another with -.
  6. The valve should now is cone-shaped to spray gasoline.
  7. Check on tightness: to remove auxiliary wires.
  8. Once again a few to work as a starter that the fuel pump has created pressure.
  9. Absolutely to wipe the valve. Within a minute it should not be observed поступания gasoline.

Check дозатора fuel


  1. A few to work as the engine (nearby 10) or a starter that the fuel total pressure was created.
  2. To uncover and a replaceable element of the air filter.
  3. To remove the big air line between the proof-reader of structure of a gas mixture and the case of throttle knot.
  4. Now it is visible запорный the valve which is necessary for extending completely upward. This process should pass all time with identical effort.
  5. By fast pressing запорного the valve resistance should not be felt. Otherwise it is necessary to replace air flowmeter.
  6. If запорный the valve manages to be extended only with great difficulty, but it very easily falls, means, in дозаторе fuel завис the distributive piston. It is necessary to replace дозатор fuel.

Check of a flowmeter of air


  1. To warm up the engine to working temperature, or to work разогретым as the engine during nearby 10 with before check.
  2. After easing of collars it is necessary to remove an air inlet sleeve between the proof-reader of structure of a gas mixture and the case of throttle knot.
  3. To check запорный the valve: it should be from outside turned to впрыскному to the pipeline, on 1,9 mm below an upper edge of a narrow cylindrical part of an air nozzle, the greatest on 3 mm is deeper.
  4. If the valve is located incorrectly, it can be tightened upwards and to correct its position, having bent fixing wire скобу below in the channel of a flowmeter of air. Not to bend at all a spring!
  5. Check up now, whether concerns запорный the valve of walls.
  6. If it so, it is necessary to weaken the central fixing screw and anew to align the valve.
  7. After this adjustment it is necessary to recheck idling and the maintenance WITH.

Check of stabilisation of frequency of idling


  1. To include ignition, to concern the distributive valve with a hand: working vibration should be felt, otherwise is faulty either the distributive valve, or the block of management of system of injection KE-III-Jetronic.
  2. To check up the distributive valve: to remove tips. To measure resistance between штекерными contacts of the distributive valve: it should be insignificant. Value "infinity" means winding rupture – defect of the distributive valve.
  3. If the distributive valve is perfectly in order, the malfunction source can be assumed in rupture of conducting or the faulty block of management. To check up and, if necessary, to replace.
  4. To connect the light-emitting diode voltmeter to both poles of a free tip of a wire.
  5. To include ignition.
  6. Вольметр should flash, in this case giving of a food from the block of management of system of injection KE-III-Jetronic is perfectly in order.

Check of the gauge of angular moving throttle заслонки

Models with a mechanical transmission

Ohmmeter contacts cannot be connected directly to gauges from which one is located below the case of throttle knot. Therefore separate only plug connection accessible from above. Measure resistance in gauge conducting:


  1. The switch of a signal of idling: to connect an ohmmeter to contacts 1 and 2 tips.
  2. Throttle заслонка in position of a mode of idling: an indicator 0 Ohm. Slightly to slightly open throttle заслонку: the indicator should pass to the Ohm.
  3. The switch of a signal of full loading: to connect an ohmmeter to contacts 2 and 3.
  4. Throttle заслонка in position of full loading: an indicator 0 Ohm. Slightly to cover throttle заслонку: the indicator should pass to the Ohm.

Check of a potentiometer throttle заслонки

Models with an automatic transmission


  1. To separate the three-polar tip of a potentiometer throttle заслонки.
  2. For check to connect an ohmmeter to contacts 1 and 2:
  3. The indicator should make 1,5 – 2,6 clod.
  4. Now to connect an ohmmeter to contacts 2 and 3:
  5. The indicator should make 0,75 – 1,3 clod.
  6. Slowly to open throttle заслонку, the ohmmeter is connected.
  7. Resistance should increase a maximum to 3,6 clod.

 The help: the potentiometer throttle заслонки can be regulated. However after that it is necessary to spend the basic adjustment automatic transmission – business for a workshop.

Check of gauges of temperature of the engine


  1. Car Audi 80 with system of injection KE-III-Jetronic is supplied by the double temperature gauge for system of injection and completely electronic system of ignition. Gaugings at these gauges are made from each of both contacts to "weight" (the block of cylinders).
  2. For check to connect an ohmmeter to one of both contacts and to "weight" (the bared metal of the block of cylinders).
  3. The received indicator of resistance depends on temperature.

Ljambda-regulation check

Though check of functioning of ljambda-regulation can be spent rather easily, however for it are necessary acc.асующий a wire and the ampermeter which is available for many fans of electronics. Or it is possible to inspect by means of a gas analyzer for definition of the maintenance WITH. The check description is more low resulted:


  1. Check should be spent at the heated-up engine.
  2. To remove the tip of a regulator of pressure, to connect made by you from two suitable tips and a wire slice the measuring adapter connecting conducting and a regulator of pressure.
  3. To separate one of acc.асующих wires and to bring to the measuring device (миллиамперный a range).
  4. To get the engine and to leave to work in an idling mode.
  5. To write down the received indicator.
  6. To extend measuring oil probe.
  7. The current should increase in a management chain.
  8. Otherwise one of ljambda-regulation components is faulty.
  9. In this case to try to separate штекерное connection to a ljambda-probe and to take a green wire to the management block nearby 20 with on "weight".
  10. If now the current in a management chain changes, means, the block of management of system of injection KE-III-Jetronc is perfectly in order, but the ljambda-probe is faulty – to replace.
  11. If will occur nothing, means, the block of management of injection system is faulty.

 The help: the basic precondition of functioning ljambda-regulation is correct basic installation of idling that means that the maintenance WITH corresponds to norm, otherwise regulation will constantly be in one of the ends of a standard range. The same conditions are created, if the mix is strongly impoverished by not considered air.

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