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Checking delivery rate > < Checking fuel pressure

Golf Mk5

Checking residual pressure
Checking residual pressure
   
l  Fuel pressure is OK and pressure tester -V.A.G 1318- is connected. Checking fuel pressure → Chapter.
–  Switch on ignition repeatedly until fuel pressure does not rise any more on pressure gauge.
–  Read fuel pressure on pressure gauge. Specification: 3.5 to 5.0 bar.
–  Watch pressure drop on pressure gauge. After 10 minutes, pressure must not drop below 3.0 bar.
If the pressure continues to drop:
–  Switch on ignition repeatedly until fuel pressure does not rise any more on pressure gauge.
  N20-10122
–  Immediately close pressure tester cut-off tap. The lever then points in direction -B-.
If the pressure drops again:
–  Check fuel pipe to high-pressure pump for leaks.
If no fault is found.
–  Renew high-pressure pump.
If pressure does not drop any further:
–  Check fuel line to fuel filter for leaks.
If no fault in the fuel line is detected:
  N20-10122
–  Check the check valve in the fuel delivery unit. Connect pressure tester -V.A.G 1318- with adapter set -V.A.G 1318/17- between fuel filter and supply pipe.
–  Open the pressure tester shut-off tap. The handle points in direction of flow.
–  Switch on ignition repeatedly until fuel pressure does not rise any more on pressure gauge.
–  Read fuel pressure on pressure gauge. Specification: 3.5 to 5.0 bar.
  N20-10148
–  After pressure has built up, immediately close pressure tester cut-off tap.
–  Watch pressure drop on pressure gauge. After 10 minutes, pressure must not drop below 3.0 bar.
If pressure drops.
–  Fuel pump non-return valve is defective, renew fuel delivery unit → Chapter.
If the pressure does not drop:
–  Pressure limiting valve in fuel filter defective. Replace fuel filter.
  N20-10139

Checking delivery rate > < Checking fuel pressure