1998 AUDI A6 AEB ATW Engines Turbocharger System Workshop Manual

21-19

Performing pressure test:

- With outlet hose -1- of VAG 1687 connected to air pressure adapter:
- Attach shop air supply line to previously installed male fitting ( Page
21
-14
.

CAUTION! - Open valve -3- between regulator valve and gauge.
- Adjust test pressure up to 0.5 bar ( CAUTION below) by turning
regulator valve -2-.
DO NOT pressurize the system above 0.5 bar!Doing so may force oil into the intake system which can damage
the engine.
- Slowly open outlet valve -4- (after gauge) to test hose connections.
- Observe pressure gauge for a drop in pressure.
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21-20

Note:
Some pressure will be lost past the throttle plate.

- Readjust test pressure to 0.5 bar ( CAUTION
above) by turning regulator valve -2-.
- Listen for any very large intake leaks.
If smoke generator was used to fill the system
with smoke:

- Inspect intake system connections for smoke at
leaks.

Note:
An ultrasonic detector may also be used to
detect extremely small leaks where smoke may
not be visible.

- Repair any leaks found.

- Remove tester.

- Remove plug from crankcase ventilation hose.

- Remove air pressure adapter.
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With VAS 5051 diagnostic tool connected:

- Erase DTC memory.
If smoke generator was not used to fill the
system with smoke:

- Apply soapy water solution or equivalent to
intake system connections.
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21-21

Note:
An ultrasonic detector may also be used to
detect extremely small leaks.

- Inspect intake system connections for leaks.

- Repair any leaks found.

- Remove tester.

- Remove plug from crankcase ventilation hose.

- Remove air pressure adapter.
With VAS 5051 diagnostic tool connected:

- Erase DTC memory.
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21-22

Rules of cleanliness


CAUTION!

Whenever carrying out any work on the fuel
supply or fuel injection systems, always
observe the following rules of cleanliness.
1. Thoroughly clean fuel system line and hose
connections and the surrounding area before
disconnecting.
2. Place removed components on a clean
surface and cover. Use plastic sheeting or paper.
Do not use fluffy rags that could leave lint!
3. Carefully cover over or seal any components
that have been opened if repairs are not carried
out immediately.
4. Install only clean parts:


Do not remove replacement parts from the
packaging until immediately before they are
to be installed.

Do not use parts that have been stored
without packaging (e.g. in toolboxes, etc.).
5. When the fuel system is opened:

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Avoid working with compressed air
whenever possible.

Avoid moving the vehicle if possible.
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21-23

Note:

Observe rules of cleanliness Page 21
-22
.

Charge air pressure control connection diagram
Page 21
-2 .

All hose connections are secured with hose
clamps that comply with factory specifications
parts catalog.

Charge air pressure system must be free of
leaks.
Always replace gaskets and self-locking nuts.
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21-24


Turbocharger, removing, installing and
overview

Part I
1 -
Bolt with collar
40 Nm (30 ft lb)Only use genuine equipment bolts parts
catalog
2 -
Gasket
Always replace
3 -
Three Way Catalytic Converter (TWC)
4 -
Nut Always replace30 Nm (22 ft lb)
5 -
Connection 30 Nm (22 ft lb)
6 -
Connection 35 Nm (26 ft lb)
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