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
   Removal of a replaceable element of the air filter
   Purge of a replaceable element of the air filter
   Replacement of a replaceable element of the air filter
   Heating of inlet air
   Heating of an inlet collector
   Inlet collector with a changeable length of a path
+ System of injection
+ 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





Inlet collector with a changeable length of a path

Fixing bolts of an inlet collector of 2,6-liter and 2,8-liter 6-cylinder engines have to be tightened in the specified sequence. Only this way it is possible to prevent a distortion of an inlet collector at installation.

At the left: gates of an inlet collector with a changeable length of a path of the 2,8-liter 6-cylinder engine are given by means of the membrane mechanism noted by an arrow.

On the right: "the valve for switching of a consecutive inlet collector" (shooter) defines this, whether the rarefied air on the membrane mechanism can get. The valve is located on the right behind in a motor compartment at an air flowmeter.

Models with the 2,8-liter 6-cylinder engine

The long inlet collector of small diameter provides a high torque already with a low frequency of rotation. The short inlet collector with big cross section, on the contrary, is necessary for high engine capacity with a high frequency of rotation of its shaft.

To combine one with another, engineers of Audi developed a new inlet collector with a changeable length of a path. Depending on operating modes at it six gates are closed and open inside. Thereby the inlet collector of different length and different cross section is provided for each cylinder: or an inlet collector for a torque (a long pipe with a small diameter), or power an inlet collector (a short pipe with big cross section). All six gates are put in action by depression and copes depending on rotation frequency: to 4000 rpm they remain closed for achievement of a high torque. Over 4000 rpm they completely open for achievement of high power. Lower than 4000 rpm by means of an inlet collector of a torque in comparison with a power inlet collector are won to 30 N • by m.
The 2,8-liter engine develops the maximum torque of 245 N • m at 3000 rpm with a condition of use of AI-95 gasoline; with application of AI-98 its torque raises to 250 N • m. In the wide range from 2000 rpm to 5500 rpm the torque of at least 220 N • m develops.

Check of action of an inlet collector

Switching of an inlet collector should be checked only in case the car does not develop the necessary power. For a start it is necessary to check manually a legkokhodnost of system of drafts and levers. Then turn of test for action: it is necessary to check at the heated-up engine.

 PERFORMANCE ORDER

  1. To start the engine and to finish rotation frequency to exceeding 4000 rpm.
  2. To watch the membrane mechanism of switching of an inlet collector:
    Draft of the drive has to depart now back.
  3. If it not so, it is necessary to check vacuum hoses for tightness. If they as it should be:
  4. To check the membrane mechanism: to put on a spare vacuum hose connection of the mechanism, strong to involve a mouth.
  5. If draft does not move and/or a lot of air is so involved, the membrane mechanism is faulty. To replace. If mechanism as it should be:
  6. To check the valve of switching of an inlet collector with a changeable length of a path: to remove both vacuum hoses from the valve. To put on a spare vacuum hose a tip to an inlet tube of the valve.
  7. Strongly to involve a mouth air from a spare vacuum hose. Retraction of air has to be impossible (impassability).
  8. To start the engine, to finish rotation frequency to much exceeding 4000 rpm.
  9. Again strongly to involve air a mouth. Now retraction of air has to be possible (passability).
  10. If still you could not find where malfunction (that in itself is rather improbable) disappears, the workshop has to be engaged in check of management.
  11. To remove protection of the engine.

Removal of an inlet collector 2,8 - the 6-cylinder engine

 PERFORMANCE ORDER

  1. To remove tips of spark plugs, to take out high-voltage wires from holders.
  2. To remove a distributive fuel-supply line together with all vpryskny nozzles (the head System of injection of MPI/MPFI).
  3. To remove an inlet air sleeve.
  4. To remove the valve of stabilization of idling or to disconnect the plug.
  5. To remove all vacuum hoses / hoses of system of ventilation of the case of a case on an inlet collector and the case of throttle knot.
  6. To remove a rope of "gas" and the plug of a potentiometer of a butterfly valve.
  7. To turn off bolts in the sequence opposite to that that it is shown in drawing above.
  8. To remove an inlet collector together with the case of throttle knot.
  9. Installation: to replace sealing laying.
  10. To tighten fixing bolts of an inlet collector according to specified in drawing at the top of sequence for four stages: First stage: 5 N • m, second stage: 10 N • m, third stage: 20 N • m, fourth stage: once again 20 N • m.

Removal of an inlet collector 2,6 - the 6-cylinder engine

 PERFORMANCE ORDER

  1. Logically removal happens to identically similar process at the 2,8-liter engine.
  2. For sequence of an inhaling of fixing bolts it is necessary to use the same, as at the 2,8-liter engine.