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Checking fuel pressure regulating valveN276 > < Checking fuel system for leaks

A4 Mk3

Checking fuel pressure (low pressure) system
Checking fuel pressure (low pressure) system
Special tools and workshop equipment required
   
t  K-Jetronic pressure tester -V.A.G 1318-
Test conditions:
l  Battery voltage at least 12.5 V.
l  Fuel filter OK.
l  Fuel tank at least 1/2 full.
l  Ignition off.
Checking residual pressure
–  Remove engine cover panel → Chapter.
  WARNING
t  Always read rules for cleanliness and instructions for working on fuel system → Chapter.
t  Follow these instructions and rules for cleanliness before starting work and while working on the fuel system.
t  To reduce the pressure in the fuel system, wrap a clean cloth around the connection and carefully loosen the connection.
  W00-0577
–  Disconnect fuel supply line -arrow- at connection point.
  A23-10331
–  Connect K-Jetronic pressure tester -V.A.G 1318- to fuel supply line -1- with suitable adapter -2-. Connect the other adapter -4- of K-Jetronic pressure tester -V.A.G 1318- to fuel supply line -3-.
  Note
  A23-10332
In this way the K-Jetronic pressure tester -V.A.G 1318- is connected into the fuel supply line.
–  Connect a → Vehicle diagnostic tester.
–  Switch on ignition.
–  Select „Engine electronics“ in vehicle self-diagnosis.
–  Then select „Basic setting“.
–  Select „Checking fuel system pressurisation pump“ from the list.
–  Press „Start“ button.
–  Fuel pumps will run for approx. 60 seconds.
–  Let fuel pumps run until maximum fuel pressure has built up.
l  Specification: at least 3.5 bar
If specification is not obtained:
Check union between pressure gauge and fuel line for leaks.
Test pressure gauge for leaks.
Check fuel lines and their connections for leaks.
Fuel filter is blocked.
Check delivery rate of fuel pump → Rep. gr.20.
  Note
Check fuel system for leaks.
  A23-10333

Checking fuel pressure regulating valveN276 > < Checking fuel system for leaks