24-48
      
Checking for leaks  
     
-  Bridge sockets 1 and 65 on the test box using 
test leads from VAG1594 A connector test kit. 
(This creates an Ground (GND) connection to 
one side of the fuel pump relay coil.) 
     
Note:  
     Once the socket are bridged the fuel pump runs 
continuously, even if the engine is not running. 
This is because the fuel pump relay receives its 
positive voltage supply via the central electrics. 
The negative voltage supply for the fuel pump 
relay comes via the cable bridge on the test box. 
     
WARNING! 
     
Fire hazard. DO NOT smoke or work near 
heaters or have anything in the area that can 
ignite fuel! 
     
-  Check injectors fuel for leaks (visual check). 
When fuel pump is running, only 1 or 2 drops 
should escape per minute from each injector. 
     
-  If fuel loss is greater, switch off fuel pump 
(remove bridge) and replace faulty injector   
Page 24
-53
 , also observe notes on   Page 24
-
53
 . 
Pa
ge 57 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 
24-51
      
-  Repeat test for fuel injectors from second bank 
of cylinders. 
     
-  If measured values for all fuel injectors are 
outside tolerance range (specification), check 
fuel pressure   Page 24
-33
 . 
     
Note:  
     When checking the injection quantity, also check 
the spray pattern. The spray pattern should be 
the same for all the injectors. 
      Installation of the fuel rail together with injectors 
is performed in the reverse sequence. The 
following points should be noted when installing:  
     
Replace O-rings at all opened connections. 
(When replacing the front O-ring, make sure 
not to remove the plastic cap from the 
injector head. The O-ring must be pulled off 
over the plastic cap.) 
     Moisten O-rings with clean engine oil. 
Pa
ge 61 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