1998 AUDI TT coolant

21-26


13 -
Gasket
Always replaceNote installed position
14 -
Coolant return line Union nut tightening torque: 30 Nm (22 ft
lb)
15 -
Nut Always replace25 Nm (18 ft lb)
16 -
Gasket Always replaceNote installed position
17 -
Banjo bolt 25 Nm (18 ft lb)
18 -
Coolant supply line
19 -
Fuse
20 -
Vacuum diaphragm For wastegate
21 -
Bolt 10 Nm (7 ft lb)
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21-30

Turbocharger, removing and installing


Note:
Replace gaskets and self-locking nuts.

Removing

WARNING!
Do NOT open A/C refrigerant circuit. - Remove noise insulation panel (arrows).
- Unbolt A/C compressor.

- Unbolt turbocharger bracket -2-.
- Disconnect oil return line -1- at turbocharger and lay aside.
- Remove air guide ducts -4- and -5- at turbocharger.
- Remove pressure line banjo fitting -3-.
- Disconnect hose from support for charge air pressure regulation valve
vacuum diaphragm.
- Unbolt bracket for coolant supply line at charge air pressure regulation
valve vacuum diaphragm.
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- Use 3094 hose clamp to pinch off coolant supply hose.
Pa
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11/18/2002 htt
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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.
Pa
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pair&id=AUDI.B5.GE02.21.1

- Use 3094 hose clamp to pinch off coolant return hose.
Pa
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11/18/2002 htt
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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:
Pa
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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.
Pa
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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
.
Pa
ge 45 of 50 Turbochar
ger s
ystem
11/18/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.GE02.21.1