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Checking residual pressure > < Checking function and voltage supply

Golf Mk5

Checking fuel pressure
Checking fuel pressure
  WARNING
The fuel supply line is under pressure! Wear protective glasses and clothing to avoid injuries and skin contact. Before loosening hose connections, wrap a cloth around the connection. Then release pressure by carefully pulling hose off connection.
   
–  Remove supply line -2- and collect escaping fuel with a cloth.
  A20-1065
–  Connect pressure tester -V.A.G 1318-, replacing fuel supply line with adapter -V.A.G 1318/1- and adapter set -V.A.G 1318/17-.
–  Close cut-off tap of pressure tester. The lever then points in position -A-.
–  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.
If fuel pressure is OK., check residual pressure → Chapter.
If the specification is exceeded:
–  Check return line between fuel filter and fuel pump for kinking and blockages.
If no fault is found.
–  Pressure limiting valve in fuel filter defective. Replace fuel filter.
If specification is not reached:
  N20-10122
–  Check fuel delivery rate upstream of fuel filter. 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.
–  Start engine and run at idling speed.
  Caution
Close the cut-off tap only slowly. At a fuel pressure of 8 bar, reopen the cut-off tap immediately to prevent damage to the pressure tester.
  N20-10148
–  Slowly close cut-off tap of pressure tester. The pressure must rise to 6.0 bar. When 6 bar have been reached, immediately reopen cut-off tap.
If pressure has risen:
–  Fuel pump is OK. Pressure limiting valve in fuel filter is defective. Renew fuel filter.
If pressure does not rise:
–  Fuel pump is defective. Renew fuel delivery unit → Chapter.
  N20-10139

Checking residual pressure > < Checking function and voltage supply