AUDI A6 2000 C5 / 2.G AEB ATW Engines Turbocharger System Service Manual
Page 41 of 50
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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Page 42 of 50
-  Use 3094 hose clamp to pinch off coolant return hose.
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Page 43 of 50
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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Page 44 of 50
     
  -  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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Page 45 of 50
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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Page 46 of 50
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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Page 47 of 50
(TWC) to turbocharger   lb)  1) Bolt strength: 10.9  
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Page 48 of 50
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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Page 49 of 50
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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Page 50 of 50
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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