Fuel System, Bleeding

Fuel System, Bleeding







- V.A.G 1318 Pressure gauge.
- V.A.G 1318/21 Adapter.
- VAS 5051 tester.
- VAS 5051/1 Adapter.
- VAS 5226 Test box.

Fuel system without return line







NOTE:
- The fuel system without return line is recognized by the sealing cap -2- at connection for return line on the fuel rail.
- To prevent damage to catalytic converter the fuel system without return line must be bled after repair work on fuel rail or on fuel lines. The vehicle must only be started after bleeding.
- Observe the rules for cleanliness.

WARNING:
- Work on the fuel system must only be performed when engine is cold.
- Fuel system is under pressure. Before opening system, place rags around the connection point. Then release pressure by carefully loosening connection.







- Close shut-off valve on special tool V.A.G. 1318/21 by turning in "-" direction up to stop.







- Unthread sealing cap from bleeder connection -2- and connect V.A.G 1318/21 Adapter instead.







- Connect V.A.G. 1318/21 Adapter and VAS 5226 catch reservoir with assistance of V.A.G. 1318 pressure gauge.

WARNING: All connection areas must be secured.







- Open shut-off valve on special tool V.A.G. 1318/21 by turning in "+" direction.
- Switch ignition on.
- Fuel pump starts up briefly.

Fuel system is bled when fuel exits into VAS 5226 catch reservoir without bubbles.

- Switch ignition off.

If the fuel pump does not operate, or fuel flows out on catch reservoir VAS 5226 continuously with bubbles:

- Connect VAS 5051 tester and select control module for engine electronics using "address word" 01. Ignition must be switched on.
- Initiate output DTM and activate Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80-. Output Diagnostic Test Mode (DTM) (Function 03)

NOTE: Fuel pump must run during activation time.

Fuel system is bled when fuel exits into VAS 5226 catch reservoir without bubbles.

- End function "03 - output Diagnostic Test Mode (DTM)" by pressing <- button.

WARNING: Fuel system is under pressure. Before opening system, place rags around the connection point. Then release pressure by carefully loosening connection.







- Close shut-off valve on special tool V.A.G. 1318/21 by turning in "-" direction up to stop.
- Remove V.A.G. 1318/21 Adapter from bleeder connection.







- Thread on sealing cap to bleeder connection -2-.