Audi A4

since 1994 release

Repair and operation of the car



A4 Audi
+ Running gear
+ Regular servicing
+ Engines
+ Turbo-supercharging
- System of an exhaust
   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 channels of absorption
+ System of injection
+ Coupling
+ Transmission and main transfer
+ Suspension bracket of wheels and steering
+ Brakes
+ Wheels and tires
+ Electrotechnical equipment
+ System of ignition
+ 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. The last section on alignment of system of an exhaust is important for assembly.

At the left: in model with the 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 one place. The 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). The 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 a 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 muffler in Audi A4 with the forward drive.

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

The system of an exhaust has to be corrected without tension

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

On the right: in quattro the fixing loop ahead on the intermediate muffler has to have a preliminary tension about 7 mm.

Detachment of a reception pipe and final collector

 PERFORMANCE ORDER

  1. Rasporny 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 by a sharp chisel. As a rule, they are made of soft material with the enclosed carving spiral. After that the carving part has to 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 of the same soft material. Do not use a nut from house stocks. Inhaling moment: 30 Nanometers.

Dismantle lambda probe

Lambda probe it has to be dismantled when replacing 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. Solid material can burst.
  3. If laying is enclosed in a flange, it needs to be replaced.
  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 for the second time. It needs to be replaced 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 the angular grinder.
  4. Other opportunity: cut a nut a chisel.
  5. Moment of an inhaling of screw connection: 25 Nanometers.

Detachment of the intermediate muffler and terminal muffler

 PERFORMANCE ORDER

  1. In original system of an exhaust both mufflers are connected by a continuous piece of a pipe.
  2. To replace one of two mufflers, it is necessary to cut a connecting pipe.
  3. Not to doubt about a sawing place, transfer length of a pipe of the new muffler to 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 installed muffler. It is better to dismantle both mufflers together.
  6. Even if you replace both mufflers – as spare parts you will be able to buy mufflers only separately.
  7. Connect pipes a double tubular collar as 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 installed with a banner can become the reason of burdensome noise. Therefore:

 PERFORMANCE ORDER

  1. Before a tightening of screw connections freely suspend system of an exhaust in fixing loops and correct:
  2. All details have to be at sufficient distance from a body.
  3. The terminal muffler (mufflers) has to be on identical distance from edges of cut in a bumper from all directions.
  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 spring.
  5. Preliminary tension of system of an exhaust for ensuring the balanced thermal expansion:
  6. In Audi with the forward drive the forward suspension bracket of the intermediate muffler has to have a preliminary tension about 7 mm.
  7. In quattro the fixing loop ahead at the intermediate muffler has to 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.