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Dynamically checking and adjusting commencement of injection > < Draining fuel filter

A4 Mk1

Checking fuel system for leaks
Checking fuel system for leaks
A leaking fuel system can cause:
t  Foam build-up or air bubbles in the supply pipe
t  Lack of power, misfiring
t  Starting problems
Special tools and workshop equipment required
   
t  Hose clamps for hoses up to 25 mm  -3094-
  W00-0079
t  Cooling system tester -V.A.G 1274-
t  Adapter -V.A.G 1274/11-
  W00-0528
–  Attach adapter -V.A.G 1274/11- to cooling system tester -V.A.G 1274-.
–  Unscrew fuel return line at injection pump and connect up hose of adapter -V.A.G 1274/11- in its place.
  A20-0337
–  Fit hose clamps up to Ø 25 mm -3094- at the following points:
t  Supply hose behind fuel filter
t  Return hose behind fuel filter
t  Return hose from injection pump
  A20-0454
–  Use hand pump on tester to create a pressure of 1.0 ... 1.5 bar.
–  If pressure drops constantly, locate leak and eliminate fault.
  Note
By moving the hose clamps from the filter to the fuel tank connections it is also possible to check the fuel hoses at the same time.
  A20-0337

Dynamically checking and adjusting commencement of injection > < Draining fuel filter