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Engine control unitJ623 > < Checking quantity injected

Golf Mk6

Checking fuel pressure regulator and holding pressure
   
Checking fuel pressure regulator and holding pressure
Special tools and workshop equipment required
t  Pressure gauge -V.A.G 1318-
t  Adapter -V.A.G 1318/9-
t  Adapter set -V.A.G 1318/17-
t  Connector -V.A.G 1318/23-
t  Remote control for V.A.G 1348 -V.A.G 1348/3A-

  Note
t  The fuel pressure regulator regulates the fuel pressure to approx. 4 bar.
t  The fuel pressure regulator is located at the fuel filter.
t  Always follow safety precautions → Chapter.
t  Observe rules for cleanliness → Chapter.
  WARNING
Fuel system is under pressure! Wear eye protection and protective clothing to avoid possible injury and skin contact. Before loosening hose connections, wrap a cloth around the connection. Then release pressure by carefully pulling hose off connection.
   
–  Separate connection for fuel supply line -3- and catch escaping fuel with a cloth.
  Note
Press in securing ring to release fuel line.
  A24-0810
–  Connect pressure tester -V.A.G 1318- with adapter -V.A.G 1318/9-and adapter set -V.A.G 1318/17- to fuel filter -1- and supply line -2-.
–  Open shut-off tap of pressure tester. The handle points in direction of flow.
–  Bleed fuel system → Chapter.
–  Start engine and run at idling speed.
–  Measure fuel pressure. Specification: approx. 4.0 bar
If the specification is not attained:
–  Switch off ignition.
–  Check delivery rate of fuel pump → Chapter.
–  If fuel pump is OK., renew fuel pressure regulator → Item.
– 
If specification is attained:
–  Switch off ignition.
–  Now check for leaks and holding pressure (entire system). Do this by observing pressure drop on gauge. After 10 minutes, there must be a residual pressure of at least 3.0 bar.
If the holding pressure drops below 3.0 bar:
–  Start engine and run at idling speed.
  N24-10054
–  Switch ignition off after the pressure has built up. At the same time, close shut-off tap of pressure tester (handle perpendicular to direction of flow) -arrow-.
–  Watch engine-side pressure drop on pressure gauge.
If the pressure drops again:
–  Check line connections, O-rings on fuel rail and injectors for leaks. → Chapter
–  Check pressure tester for leaks.
  Note
Before removing pressure tester, place a cloth around the connections to be loosened.
If the pressure does not drop:
–  Check line connections to fuel tank and non-return valve of fuel pump. → Chapter
–  If non-return valve is OK., renew fuel pressure regulator → Item.
–  Bleed fuel system → Chapter.
  N24-0618

Engine control unitJ623 > < Checking quantity injected