Page 31 of 90
24-27
      
Idle speed, checking
 
     
Test conditions  
     
No leaks in exhaust system 
     Coolant temperature at least 80 C 
     
Electrical consumers switched off (radiator 
fan must not run during the check) 
     A/C switched off 
     Pressure gauge not connected 
     Selector lever in position P or N (vehicles 
with automatic transmission) 
     
Checking idle speed  
     
Notes:  
     The idle speed cannot be adjusted.
     The idle speed is tested during the basic setting 
of the engine. 
Pa
ge 31 of 90 Motronic Multi
port Fuel In
jection 
(MFI
) system, servicin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.24.1 
     
        
        Page 33 of 90
24-28
      
-  Check DTC memory   Page 01
-15
 . The DTC 
memory must be clear. If necessary, repair any 
malfunctions and erase the DTC memory. 
Switch off the engine, then start up again. Take 
vehicle for a test drive and check DTC memory 
again to make sure it is clear. 
     
-  Run engine at idle speed. 
     
CAUTION! 
     
The electric radiator fan should not be 
running. Rapid data transfer 
HELP
Select function XX
    
Indicated on display  
-  Press buttons -0- and -4- to select function "Basic Setting" and confirm 
entry with -Q- button. 
Basic settin
g 
Input displa
y group number XXX
    
Indicated on display  
-  Press buttons -0- -5- and -6- to select "Display group number 056" and 
confirm entry with -Q- button. 
Pa
ge 33 of 90 Motronic Multi
port Fuel In
jection 
(MFI
) system, servicin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.24.1 
     
        
        Page 69 of 90
24-59
      
Mass Air FLow (MAF) sensor -G70, 
checking
 
     
Requirements  
     
Coolant temperature at least 80 C (175 F) 
     
Electrical consumers switched off (radiator 
fan must not run during test) 
     A/C switched off 
     Fuse for mass air flow sensor OK 
     
       Electrical Wiring Diagrams, Troubleshooting & 
Component Locations   
     
Checking function  
     
-  Connect vehicle diagnostic, testing and 
information system VAS5051 or VAG1551 scan 
tool and select engine electronics control 
module by entering address word "01"   Page 
01
-9 . When doing this the engine must be at 
idle. 
Pa
ge 69 of 90 Motronic Multi
port Fuel In
jection 
(MFI
) system, servicin
g
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU04.24.1