Fuel Delivery Pump, 8-Cylinder, Checking Delivery Quantity

FSI Engines

Fuel Delivery Pump, 8-Cylinder, Checking Delivery Quantity

Special tools, testers and auxiliary items required

• Pressure Gauge K-Jetronic (V.A.G 1318)

• Pressure Gauge Adapter (V.A.G 1318/10-12)

• Remote Control (V.A.G 1348/3A) with Adapter Cable (V.A.G 1348/3-3)

• Measuring container, fuel-resistant

Procedure





• Battery voltage min. 12.5 V.

• Is the Fuel Pump Control Module (J538) OK; check under "Guided Fault Finding" with Vehicle Diagnosis, Testing and Information System (VAS 5051B).

• Fuel filter OK.

• Fuel tank at least 1/4 filled.

• Ignition switched off.


Observe safety precautions. Refer to => [ Safety Precautions ] Fuel Supply System.

- Remove the cover of right luggage compartment side trim - arrows -.





- Remove cover - 2 - above battery.





• Ignore - 1 -.

- Remove the luggage compartment floor mat.

- Unbolt cover for left locking flange - arrows -.





- Disconnect electrical harness connector - 2 - at left locking flange.





• Ignore - 1 -.

- Unbolt cover for right locking flange - arrows -.





- Disconnect electrical harness connector - 2 - at right locking flange.





• Ignore - 1 -.

- Connect Remote Control for VAG 1348 (V.A.G 1348/3A) with Adapter Cable (V.A.G 1348/3-3) and adapter cables from Connector Test Set (V.A.G 1594C) to terminal - 4 - (ground) on left and right delivery unit.





- Route Remote Control (V.A.G 1348/3A) switch forward in engine compartment.

- Connect alligator clip to ground point in engine compartment.

- Connect terminal - 1 - (positive) on left and right delivery unit using a self-made adapter cable to vehicle battery "+". For safety reasons, install a fuse - A - (10 A) in the wiring.

- Remove fuel filler cap from fuel filler tube.

- Pull rear engine cover off - arrows -.






Fuel system is under pressure! Before opening system, place clean rags around the connection. Then release pressure by carefully loosening the connection.

- Disconnect fuel supply line - arrow - on distribution piece.






Note rules of cleanliness for working on the fuel injection system. Refer to => [ Clean Working Conditions ] Fuel Supply System.

- Disconnect fuel line - arrow -.

- Connect Fuel Inj. Pressure Gauge-CIS (V.A.G 1318) with Adapter (V.A.G 1318/11) and (V.A.G 1318/12) in fuel line.





- Connect assisting hose - arrow - on pressure gauge and hold it in a measuring container.

- Open shut-off valve of pressure gauge set. The lever points in the direction of flow.

- Generate pressure in the fuel system by pressing the switch of the remote control and slowly closing the shut-off valve of the pressure gauge.

• Specified value: 4 bar positive pressure.

- From this point on do not move position of shut-off tap.

- Empty the measuring container.

- Press the switch on the remote control for 15 seconds.





- Compare quantity of fuel delivered with minimum delivery rate in diagram (cm3/15s).

• Voltage at fuel pump with engine stopped and pump running is approximately 2 volts less than battery voltage.

If minimum delivery quantity is not obtained, the following malfunctions may be present:

• Fuel lines pinched.

• Fuel filter clogged.

• Fuel pump faulty.

• Because the quantity of fuel delivered does not decrease significantly when one of the fuel pumps malfunctions - due to the internal lines in the tank - a faulty pump cannot be diagnosed accurately by measuring the quantity delivered.

In this case, proceed as follows:

- Remove electrical adapter cable at each fuel delivery unit.

- Measure the fuel delivery rate at opposite fuel delivery unit.

If the fuel delivery rate by the individually measured fuel delivery unit is considerably less than the specified value:

- Replace affected fuel delivery unit.

Assembly is in reverse order of removal, note the following:

- Attach fuel line to engine