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Checking current draw > < Checking function and voltage supply

Golf Mk6

Checking fuel delivery rate
Checking fuel delivery rate
Test prerequisites
l  Voltage supply OK.
l  Fuel pressure regulator and holding pressure OK → Chapter.
l  Fuel filter OK.
–  Remove filler cap from fuel tank filler neck.
–  Open cover of relay and fuse holder of engine compartment E-box.
–  Pull fuse SB33 out of socket F33 of fuse holder.
   
–  Connect remote control for V.A.G 1348 -V.A.G 1348/3A- with adapter cable -V.A.G 1348/3-3- to right terminal of fuse socket F33.
–  Tape off 2nd connector contact of the adapter cable -V.A.G 1348/3-3- with insulating tape -arrow- to prevent short circuits.
–  Connect crocodile clip to vehicle battery (+).
  Note
Delivery rate of fuel pump must be measured at 4 bar. Therefore, test fuel pressure before measuring delivery rate.
  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.
  A20-1095
–  Pull return line -1- off 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 container.
–  Operate remote control for V.A.G 1348 -V.A.G 1348/3A- for approx. 5 seconds to fill fuel filter.
–  Empty measuring container.
–  The delivery rate of the fuel pump depends on the voltage. Therefore connect the multimeter to the battery.
–  Operate remote control for 30 seconds while measuring battery voltage.
  N20-0526
–  Compare quantity of fuel delivered with specification.
*) Minimum delivery rate cm3/30 s
**) 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 12.5 volts is measured at the battery. As the voltage at the pump is approx. 2 volts less than the battery voltage, this will equate to a minimum delivery rate of 600 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.
  N20-10138
–  Pull supply line -1- off inlet to fuel filter.
  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 container.
–  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 4 bar is displayed on pressure gauge. From this point on do not move position of shut-off tap.
–  Empty measuring container.
–  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 → Chapter.
–  Reconnect all disconnected fuel lines.
–  Bleed fuel system → Chapter.
If fuel delivery rate has been attained, but you nevertheless suspect a fuel supply system fault, e.g. intermittent failure of fuel supply system:
–  Measure current draw of fuel pump → Chapter.
  N20-0531

Checking current draw > < Checking function and voltage supply