AUDI A4 1998 B5 / 1.G AFC Engine Fuel Syst

AUDI A4 1998 B5 / 1.G AFC Engine Fuel Syst A4 1998 B5 / 1.G AUDI AUDI https://www.carmanualsonline.info/img/6/1020/w960_1020-0.png AUDI A4 1998 B5 / 1.G AFC Engine Fuel Syst

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AUDI A4 1998 B5 / 1.G AFC Engine Fuel Syst 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

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AUDI A4 1998 B5 / 1.G AFC Engine Fuel Syst Note:  
If during subsequent pressure tests, fuel leaks from the pressure regulator 
vacuum connector, replace it.  lines (tester handle shown in open position). 
-  Disconnect vacuum line (from fuel

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AUDI A4 1998 B5 / 1.G AFC Engine Fuel Syst 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:

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AUDI A4 1998 B5 / 1.G AFC Engine Fuel Syst -  Check return line for damage (e.g. pinched 
locations), and replace if necessary. 
     
Note:  
     During subsequent testing the engine should not 
run for an unnecessarily long time with the 
v

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AUDI A4 1998 B5 / 1.G AFC Engine Fuel Syst 24-22
      
- Let engine idle. 
     
   This will automatically halt the output DTM 
sequence. 
     
-  Switch off all electrical consumers (A/C etc.).
     
-  Connect vacuum hose to pressure regu

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AUDI A4 1998 B5 / 1.G AFC Engine Fuel Syst 24-23
      
Residual pressure, checking  
      Residual pressure 10 minutes after stopping 
engine:  
     
With cold engine: 2.2 bar (32 psi) minimum
     With a hot engine: 3.0 bar (44 psi) minimu

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AUDI A4 1998 B5 / 1.G AFC Engine Fuel Syst       If there are no leaks and the fuel pump check 
valve is OK:  
     
-  Replace fuel pressure regulator and repeat 
residual pressure test. 
Pa
ge 7 of 7 Fuel s
ystem 
pressure and residual 
pres