engine oil AUDI A4 1998 B5 / 1.G AEB ATW Engines Turbocharger System Workshop Manual
Page 7 of 50
21-6
      
Test conditions:  
     
Check DTC memory Repair Manual, 1.8 
Liter 4-Cyl. 5V Turbo Fuel Injection & 
Ignition, Repair Group 01 
     Perform output diagnostic test mode 
(function 03) 
     Minimum engine oil temperature: 60 C 
(140 F) 
     
All vacuum connections are free of leaks 
     
Test procedure  
    
-  Using T-fitting, connect VAG1397A turbocharger tester test hose to 
front of intake manifold. 
-  Guide test hose over rear corner of hood through right window opening 
into vehicle interior. 
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Page 25 of 50
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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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 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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