AUDI A3 1998 8L / 1.G AEB ATW Engines Turbocharger System Service Manual

21-31

- Remove intake air duct between cowl and air
cleaner housing.

- Remove air cleaner housing cover.

- Remove the following lines/harness connectors:
1 - At wastegate bypass regulator valve -N75-
2 - At Evaporative Emissions (EVAP) purge regulator valve -N80-
3 - At power output stage -N122-
4 - At Mass Air Flow (MAF) sensor -G70-
- Remove hose connections and remove air cleaner housing (arrows).
- Remove engine covers.

- Unbolt crankcase ventilation hose -1- at cylinder head cover and heat
shield.
- Unbolt both oil supply line bolts -3-.
- Remove heat shield -4-.
- Remove sleeve -2- from coolant return hose.
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- Use 3094 hose clamp to pinch off coolant return hose.
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21-32

- Remove coolant return hose at line to
turbocharger. Line remains bolted to
turbocharger.

- Unbolt oil supply line -7- at turbocharger.

Note:
The exhaust flexpipe must not be bent more than
10 , otherwise it may be damaged.
- Unbolt Three Way Catalytic Converter (TWC)
from turbocharger -6-.

- Unbolt turbocharger from exhaust manifold -5-
.

- Move turbocharger to side and remove coolant
supply line banjo fitting.

- Remove turbocharger.

Installing
Installation is the reverse of removal, noting the
following:

- Perform the following steps before tightening
turbocharger:
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- Loosely bolt coolant supply line to vacuum
diaphragm for charge air pressure regulation
valve.

- Tighten banjo fitting, then tighten mounting
bolt for bracket to proper torque.
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21-33

Note:
Add oil to turbocharger through oil supply line
connection flange.

- Fill up coolant Page 19
-4 .

WARNING!

The cooling system is pressurized when the
engine is warm. When opening the expansion
tank, wear gloves and other appropriate
protection, cover the cap with a cloth and
open carefully to relieve system pressure
slowly.

Note:
After installing the turbocharger, let engine idle
for approx. 1 minute without increasing engine
speed. This ensures adequate oil supply to the
turbocharger.

- Check engine oil level Page 17
-27
.
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21-34

Tightening torques

Component
Tightening
torques
Oil return line to turbocharger 10 Nm (7 ft
lb)
Turbocharger bracket to
turbocharger (bolt and washer
assembly M8)
1) 40 Nm (30 ft
lb)
Turbocharger bracket to cylinder
block 45 Nm (33 ft
lb)
Oil feed line to turbocharger 25 Nm (18 ft
lb)
Coolant supply pipe bracket to
turbocharger 10 Nm (7 ft
lb)
Oil supply line bracket to cylinder
head 20 Nm (15 ft
lb)
Coolant supply line to
turbocharger 25 Nm (18 ft
lb)
Crankcase ventilation line to
cylinder head 10 Nm (7 ft
lb)
Coolant return line to
turbocharger 30 Nm (22 ft
lb)
Turbocharger to exhaust
manifold 35 Nm (26 ft
lb)
Three Way Catalytic Converter 30 Nm (22 ft
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(TWC) to turbocharger lb) 1) Bolt strength: 10.9
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21-35


Charge air cooler components, removing
and installing

Note:

All hose connections are secured with hose
clamps parts catalog. charge air pressure system must be free of
leaks.
1 -
Air duct
2 -
Grommet
3 -
Hose
Between charge air cooler and air guide in
cowl
4 -
Hose Between intake manifold and charge air
cooler
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21-36


5 -
Bracket
Riveted to body
6 -
Grommet With sleeve
7 -
Charge air cooler Removing and installing Page 21
-37
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21-37

Charge air cooler, removing and
installing


Lock carrier in service position Page 13
-
1 .

Removing

- Remove upper air duct at charge air cooler.

Installing
Installation is the reverse of removal. - Remove noise insulation panel (arrows).
- Disconnect air guide at charge air cooler.
- Remove lower air duct at charge air cooler.
- Remove charge air cooler from below.
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