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Check fuel pressure regulator > < Residual pressure and fuel pressure regulator - check

Polo Mk4

Test sequence
Test sequence
–  Remove fuse holder cover.
   
–  Remove fuse 41 from the (Fuel pump (pre-supply pump) -G6-) fuse holder.
  WARNING
The fuel system is under pressure. Before loosening hose connections or opening checking junction, place a cloth around them. Then, eliminate the pressure, by carefully removing the hose and loosening the closing screw.
BAH engine
  N24-1481
–  Loosen the fuel supply pipes (black) -1- (press the unlock key).
BPA/CCRA engines
  R10-10008
–  Loosen the fuel supply pipes (black) -1- (press the unlock key).
  Note
To unfasten fuel lines, press the safety key.
  R10-10009
–  Connect the Pressure gauge -VAG 1318- with the Adapting set -VAG 1318/17- and -VAG 1318/9-.
–  Open the Pressure gauge -VAG 1318-valve. The valve will point towards the direction of flow.
–  Install fuse 41 (Fuel pump (pre-supply pump) -G6-) to the fuse holder.
–  Start the engine and keep it idling.
–  Measure fuel pressure. Theoretical value: approx. 3.0 bar (BAH engine) and 4.2 (BPA/CCRA).
If the theoretical values is not obtained:
–  Turn ignition off.
–  Check that the Fuel pump (pre-supply pump) -G6- is generating and maintaining this pressure → Chapter.
–  Check fuel pressure regulator → Chapter.
If the theoretical values is obtained:
–  Turn ignition off.
–  Check sealing and residual pressure, whilst keeping an eye on the pressure drop on the Pressure gauge -VAG 1318-. After 10 minutes, a minimum pressure of 2.0 bar must be obtained.
If residual pressure drops below 2.0 bar:
–  Start the engine and keep it idling.
  N24-1470
–  When the pressure is reached, turn ignition off, while closing the Pressure gauge -VAG 1318- valve (valve transverse to the blockage direction -arrow-).
–  Check the pressure drop on the Pressure gauge -VAG 1318-.
If the pressure drops again:
–  Check hose connections for Fuel pump (pre-supply pump) -G6- to the Pressure gauge -VAG 1318-.
–  Check the Pressure gauge -VAG 1318- for leaks.
  Note
Before removing the Pressure gauge -VAG 1318-, once again place cloths around the hose junctions.
If the pressure does not drop:
–  Check the Fuel pump (pre-supply pump) -G6- → Chapterretention valve.
–  Check fuel pressure regulator → Chapter.
  N24-0618

Check fuel pressure regulator > < Residual pressure and fuel pressure regulator - check