Audi A4

since 1994 of release

Repair and car operation



A4 Audi
+ Running gear
+ Regular servicing
+ Engines
+ Turbo-supercharging
- Exhaust system
   Versions of systems of an exhaust
   Check of a suspension bracket and condition of system of an exhaust
   Replacement of system of an exhaust
   Dismantle of separate details
+ cooling System
+ Fuel tank and fuel pump
+ Air filter and absorption channels
+ injection System
+ Coupling
+ Transmission and main transfer
+ Suspension bracket of wheels and steering
+ Brakes
+ Wheels and tires
+ Electrotechnical equipment
+ ignition System
+ Lighting
+ Alarm equipment
+ Tools and devices
+ Heating and ventilation
+ body Details
+ Salon
Search of malfunctions
Technical characteristics





Dismantle of separate details

In the following sections it is described, how separate connections of system of an exhaust are disconnected from each other. For assembly the last section on alignment of system of an exhaust is important.

At the left: in model with a drive on forward wheels with the six-cylinder engine only one catalytic converter (3). Exhaust pipes from both blocks of cylinders (2) enter in front of the catalytic converter into one place. Figure «1» showed a double collar.

On the right: at the six-cylinder engine in the quattro model two separate catalytic converters (2 and 3). Figure «1» showed a double collar.


Here by an arrow it is shown screwed in a final collector a lambda probe in the four-cylinder engine with working volume of 1,6 l.

Various rubber suspension brackets of system of an exhaust

At the left: a forward suspension bracket of the terminal exhaust silencer in Audi A4 with a forward drive.

On the right: one of back suspension brackets of the terminal exhaust silencer in A4 quattro.

The system of an exhaust should be corrected without a tension

At the left: in Audi with a forward drive the forward suspension bracket should have a preliminary tension about 7 mm.

On the right: in quattro the fixing loop ahead on the intermediate exhaust silencer should have a preliminary tension about 7 mm.

Detachment of a reception pipe and final collector

 PERFORMANCE ORDER

  1. Raspornye hairpins on which fixing nuts of a reception pipe settle down, easily break off, if with pressing strongly rusted nut unscrews.
  2. Therefore: process anticorrosive spray screw connection or (it is frequent better):
  3. Destroy nuts a sharp chisel. As a rule, they are made of a soft material with the enclosed carving spiral. After that the carving part should be separately removed from a carving of a rasporny hairpin.
  4. New nuts in a set for fastening of an exhaust system are also made from this a soft material. Do not use a nut from house stocks. Inhaling moment: 30 Nanometers.

Dismantle lambda probe

Lambda probe it should be dismantled at replacement of the catalytic converter (or the probe).

 PERFORMANCE ORDER

  1. Hang out wire arms on a body, disconnect sockets (see a wire on all its length).
  2. Unscrew a probe.
  3. At installation grease a lambda probe with anticorrosive greasing. Thus greasing should not get to area of openings of a body of a probe. Inhaling moment: 50 Nanometers.

Detachment of a triangular flange (with a spring)

 PERFORMANCE ORDER

  1. Weaken three screw connections on a connecting flange.
  2. If the sealing ring is enclosed, but on it it is necessary to pay special attention – it should not fall to a floor. The firm material can burst.
  3. If in a flange laying is enclosed, it is necessary to replace it.
  4. Moment of an inhaling of bolts: 25 Nanometers.
  5. At an inhaling it is necessary to pay attention to that bolts were tightened in parallel the friend
    to the friend.

Detachment of a double tubular collar

The double tubular collar faultlessly connects two cut-off pieces of a pipe and is easily disconnected. Important: the double tubular collar cannot be used in the second time. It is necessary to replace it even after weakening of screw connection.

 PERFORMANCE ORDER

  1. Note an assembly arrangement of a collar for the subsequent assembly.
  2. Disconnect screw connections of a double tubular collar; for this purpose process a carving rust solvent.
  3. If screw connection cannot be disconnected thus, separate a bolt from a nut by angular grinding car.
  4. Other possibility: cut a nut a chisel.
  5. Moment of an inhaling of screw connection: 25 Nanometers.

Detachment of the intermediate exhaust silencer and terminal exhaust silencer

 PERFORMANCE ORDER

  1. In original system of an exhaust both exhaust silencers are connected by a continuous piece of a pipe.
  2. To replace one of two exhaust silencers, it is necessary to cut a connecting pipe.
  3. Not to doubt about a cutting place, transfer length of a pipe of the new exhaust silencer on a pipe of the old. For confidence leave a stock approximately in 10 mm. In this case at installation there will be a little place for adjustment.
  4. Cut a pipe a saw for metal whenever possible at right angle.
  5. Because of a lack of a place it is hardly possible to make it on the established exhaust silencer. It is better to dismantle both exhaust silencers together.
  6. Even if you replace both exhaust silencers – as spare parts you can buy exhaust silencers only separately.
  7. Connect pipes a double tubular collar how it was already told (from a warehouse of spare parts). Inhaling moment: 25 Nanometers.

Alignment of system of an exhaust

The system of an exhaust established with reheavy, can become the reason of burdensome noise. Therefore:

 PERFORMANCE ORDER

  1. Before a tightening of screw connections freely suspend exhaust system in fixing loops and correct:
  2. All details should be at sufficient distance from a body.
  3. The terminal exhaust silencer (exhaust silencers) from all directions should be on identical distance from cut edges in a bumper.
  4. Tighten an arm on a transmission with the moment of an inhaling of 25 Nanometers. Pay attention to correctness of assembly of a sleeve and a spring.
  5. Preliminary tension of system of an exhaust for ensuring the balanced thermal expansion:
  6. In Audi with a forward drive the forward suspension bracket of the intermediate exhaust silencer should have a preliminary tension about 7 mm.
  7. In quattro the fixing loop ahead at the intermediate exhaust silencer should have a preliminary tension about 7 mm.
  8. In the end tighten all screw connections of system of an exhaust, beginning in front. The moments of an inhaling are specified in the previous sections.