24-20
 
     
Fuel system pressure and 
residual pressure, checking 
     
CAUTION! 
     
Fire hazard! Do not smoke, work near heaters 
or open flame, or have anything in the area 
that could ignite fuel. 
     
Checking requirements:  
     
Fuel pump relay OK; checking   page 24
-24
     
Fuel pump OK: 
     
       Repair Manual, 2.8 Liter V6 2V Engine 
Mechanical, Engine Code(s): AFC, Repair Group 20
   
     
Correct fuel filter installed 
     Battery positive voltage (B+): 12 volts 
minimum 
     
Checking system pressure  
    
- 
Connect VAG 1318 pressure tester between fuel supply and fuel return 
Pa
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pressure and residual 
pressure, checkin
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24-21
      
-  Use scan tool "Output Diagnostic Test Mode" 
function 03 to trigger Fuel Pump (FP) relay -J17-
 Repair Group 01.       If fuel pump does not run:  
     
-  Check fuel pump:
     
       Repair Manual, 2.8 Liter V6 2V Engine 
Mechanical, Engine Code(s): AFC, Repair Group 20
   
     
   Specified value: 3.8 to 4.2 bar (55 - 61 psi)
      If the specified value is not obtained:  
     
-  Replace fuel pressure regulator and perform 
pressure test again. 
      If the value is again not obtained:  
     
-  Check whether fuel pump or supply line is 
damaged (e.g. pinched), and replace if 
necessary. 
      If the specified value is exceeded:  
     
Pa
ge 3 of 7 Fuel s
ystem 
pressure and residual 
pressure, checkin
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.FU01.24.4