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Checking current draw > < Checking holding pressure

Polo Mk5

Checking fuel delivery rate
Checking fuel delivery rate
Test prerequisites
l  Voltage supply OK.
l  Remote control for V.A.G 1348 -V.A.G 1348/3A- is connected.
Test procedure
  Note
Delivery rate of fuel pump must be measured at 3 bar. Therefore, test fuel pressure before measuring delivery rate.
–  Remove filler cap from fuel tank filler neck.
   
–  Pull off return line -1- from fuel pressure regulator.
  Note
Press in securing ring to release fuel line.
–  Connect adapter set -V.A.G 1318/17- to fuel pressure regulator and hold end of adapter in measuring glass.
–  Operate remote control -V.A.G 1348/3A- for approx. 5 seconds to fill fuel filter.
–  Empty measuring glass.
–  The fuel delivery rate of the fuel pump depends on the voltage, therefore connect multimeter to both outer contacts (connector remains connected) of fuel pump using adapter cables from auxiliary measuring set -V.A.G 1594C-.
–  Operate remote control for 30 seconds while measuring battery voltage.
  N20-0526
–  Compare quantity of fuel delivered with specification.
1)  Minimum delivery cm3/30 seconds
2)  Voltage at fuel pump with engine not running and pump running (approx. 2 volts less than battery voltage).
Example:
During the test a voltage of 10.5 volts is measured. At this pump voltage, the minimum delivery rate is 540 cm3/30 s.
If minimum delivery rate is not attained:
–  Check supply line to filter for possible restrictions (kinks) or blockages.
If fuel line is OK
–  Check fuel delivery rate before fuel filter.
  WARNING
Fuel supply lines are under pressure! Wear eye protection and gloves 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.
  N20-0134
–  Pull off supply line -1- from fuel filter inlet.
  Note
Press in securing ring to release fuel line.
–  Connect pressure tester -V.A.G 1318- using adapters -V.A.G 1318/17- as shown.
–  Push adapter -V.A.G 1318/1- onto adapter -V.A.G 1318/11- of pressure tester and hold it in measuring glass.
–  Open shut-off tap of pressure tester. The lever then points in direction of flow -A-.
–  Operate remote control for V.A.G 1348 -V.A.G 1348/3A-. Then slowly close shut-off tap until a pressure of 3 bar is displayed on pressure gauge. From this point on do not move position of shut-off tap.
–  Empty measuring glass.
–  Operate remote control again for 30 seconds. Compare delivery rate with the value determined in the first measurement.
If the minimum delivery rate is now attained:
–  Renew fuel filter.
If the minimum delivery rate is again not attained
–  Remove fuel delivery unit and check filter strainer for soiling.
Only if still no fault has been detected:
–  Renew fuel delivery unit.
  N20-0531

Checking current draw > < Checking holding pressure