Fuel Delivery and Air Induction: Service and Repair

Fuel System, Bleeding

Special tools, testers and auxiliary items required

• Adapter (V.A.G 1318/20)






• Diesel extractor (VAS 5226)






• Vehicle diagnostic tester

Perform the following:

• If fuel supply system was opened, it must always be bled before starting engine.

• If fuel supply system is not bled, catalytic converter will be damaged.

• Follow the guidelines for cleanliness. Refer to => [ Clean Working Conditions ] Clean Working Conditions.


Fuel system is under pressure!

• Wear protective goggles and protective clothing in order to avoid injury and contact with the skin.

• Before loosening line connections, place cloths around the connection point. Then release pressure by carefully pulling off the line.

- Turn valve at T-piece counterclockwise until it is completely open.






- Connect the adapter (V.A.G 1318/20-1) to the adapter (V.A.G 1318/20).

- Hand-tighten the adapter (V.A.G 1318/20) onto the bleed valve.

- Remove the cap - arrow - from the bleed valve.






- Connect the suction pump (VAS 5226) hose as illustrated.






- Turn valve (at T-piece) clockwise into bleeder valve to stop.

- Check the adapter and hose connection for leaks.

- Connect the Vehicle Diagnosis Tester - 1 -.






- Connect the diagnostic cable connector - 2 - to the diagnostic connection inside the footwell on the driver side.

- On the touch screen, select the following:

OBD

OBD ->

Engine electronics ->

Output diagnostic test ->

- Keep pressing -> until the fuel pump relay activates. This activates the fuel pump.

- Let the diagnosis run until fuel flows out of the ventilation valve without bubbles.

- End the output diagnostic test.

• If the output diagnostic test mode is interrupted, the engine must be started for a short time before the mode can be accessed again. Output diagnostic test mode is automatically cancelled after 60 seconds.

- Turn valve at T-piece counterclockwise until it is completely open.






- Clamp off the suction pump (VAS 5226) hose, (use, for example hose clamps up to 25 mm diameter (3094) ) and remove it from the adapter (V.A.G 1318/20-1).

- Remove the adapter (V.A.G 1318/20) from the bleed valve.