Audi Workshop Service and Repair Manuals

Fuel system without return pipe   Note t  In order to prevent damage to the catalytic converter, the fuel system without return pipe must be bled after working on the fuel pipes or the fuel filter. The vehicle must only be started after bleeding t  With this type of fuel system, there is no return pipe on the fuel rail. Refer to: Dismantling and assembling fuel rail with injectors → Chapter. t  Observe the rules for cleanliness → Chapter.   WARNING t  Work on the fuel system must only be performed when the engine is cold. t  The fuel system is pressurised. Before opening the system place a cloth around the connection. Then release pressure by carefully loosening the connection.

–  Turn cut-off valve on adapter for K-Jetronic tester -V.A.G 1318/21- as far as possible towards „–“.

–  Screw adapter for K-Jetronic tester -V.A.G 1318/21- onto bleeder connection -2-.   WARNING t  Work on the fuel system must only be performed when the engine is cold. t  The fuel system is pressurised. During the following work steps, always make sure that there are no leaks at any connections.

–  Now connect adapter for K-Jetronic tester -V.A.G 1318/21- with diesel extractor -VAS 5226- using K-Jetronic pressure tester -V.A.G 1318-.   WARNING All connections must be fastened securely.

–  Turn cut-off valve on adapter for K-Jetronic tester -V.A.G 1318/21- towards „+“ to open valve. –  Switch on ignition. –  Fuel pump will run now for several seconds. –  As soon as bubble-free fuel flows out of diesel extractor -VAS 5226-, switch ignition off immediately. –  This indicates that fuel system has been bled.   Note

t  Before unscrewing the adapter for K-Jetronic tester -V.A.G 1318/21-, the cut-off valve must be closed by turning it towards „–“. t  After completing bleeding process the protective cap has to be screwed onto the bleeder connection. –  If fuel pump does not start up or fuel flowing out of diesel extractor -VAS 5226- is not yet free of bubbles: –  Activate fuel pump via final control diagnosis. Starting final control diagnosis   Note t  Fuel pump will be activated automatically when final control diagnosis is started. t  Final control diagnosis can only be performed when engine is not running and ignition is switched on. t  Final control diagnosis is terminated if next step is not selected after an actuation time of 1 minute, if engine is started or if an engine speed pulse is detected. t  Before restarting the final control diagnosis the engine must be started and the ignition must be switched off and on again. –  Connect vehicle diagnostic tester and select engine electronics control unit. When doing this, the ignition must be switched on. –  Select diagnostic function „Final control diagnosis“. –  Fuel pump will run for approx. 1 minute. As soon as bubble-free fuel flows out of diesel extractor -VAS 5226-, switch ignition off immediately. This indicates that fuel system has been bled.   WARNING The fuel system is pressurised. Before opening the system place a cloth around the connection. Then release pressure by carefully loosening the connection.   Note

t  Before unscrewing the adapter for K-Jetronic tester -V.A.G 1318/21-, the cut-off valve must be closed by turning it towards „–“. t  After completing bleeding process the protective cap has to be screwed onto the bleeder connection.