Audi Workshop Service and Repair Manuals

Removing and installing high-pressure pump Special tools and workshop equipment required

t  Torque wrench -V.A.G 1331-

t  Ratchet -V.A.G 1331/1-

t  Socket, 14 mm -3150- Removing   WARNING The fuel system operates at extremely high pressure. This can cause injury. t  The fuel pressure in the high-pressure section of the injection system must be reduced to a residual pressure prior to opening the system → Chapter. t  Wrap a clean cloth around the connection and carefully loosen the connection to allow the residual pressure to dissipate.   Note t  The high-pressure pump should only be removed and installed when the engine is cold. t  When installing the high-pressure fuel pump, it is essential to ensure that no dirt enters the fuel system. t  Use a cloth to catch escaping fuel. t  The O-ring must always be renewed. t  Always ensure that the high-pressure fuel pipes are free of tension when tightening the connections. –  Remove air cleaner (bottom section) → Chapter.

–  Unscrew bolts -arrows- and remove guard plate -1-.

–  Unplug electrical connectors -1- and -6-. –  Detach fuel supply hose -2- and unscrew connection -5-. –  Remove bolts -3- and -4- from retaining clips. –  Remove bolts -arrows- and lift high-pressure pipe carefully.   Note t  Do not bend fuel pipes to a different shape. t  Do NOT bend open retaining clamps for fuel pipe. t  If one of the retaining clamps has been bent open or the fuel pipe has to be renewed, the retaining clamps must also be renewed. –  Carefully pull out high-pressure pump.

–  Pull roller tappet -1- out of housing. Installing Installation is carried out in the reverse order; note the following:   Note t  The connections of the high-pressure pipe must not be damaged. t  Do not bend fuel pipes to a different shape. t  Do NOT bend open retaining clamps for fuel pipe. t  If one of the retaining clamps has been bent open or the fuel pipe has to be renewed, the retaining clamps must also be renewed. –  Renew O-ring for high-pressure pump.

–  Check roller tappet -1- for damage and renew if necessary. –  Lightly lubricate roller tappet with oil and insert it so that lug -arrow A- slides into guide notch -arrow B-.   Note The roller tappet must be positioned at the lowest point when installing the high-pressure pump. –  Rotate crankshaft in direction of engine rotation by turning bolt for vibration damper, and at the same time press roller tappet into cylinder head until it reaches its lowest point. –  Only lift high-pressure pipe slightly to fit high-pressure pump. –  Insert high-pressure pump into housing.

–  Hand-tighten the bolts -arrows- as far as the flange. –  Now tighten bolts in diagonal sequence to specified torque (approx 1 turn each until high-pressure pump makes contact).   Note The pump can be damaged if it is tightened too much on one side (keep it straight). t  Tightening torque: refer to exploded view of high-pressure pump → Chapter. –  Tighten union nut -5- on fuel supply line hand-tight. Align so that parts are free of tension. –  Connect fuel supply hose -2- again.

–  Tighten bolts -3- and -4- on retaining clips. –  Plug in electrical connectors -1- and -6-.

–  Tighten high-pressure pipe to specified torque → Fig..

–  Install guard plate -1-. –  Install air cleaner (bottom section) → Chapter.   Note Check fuel system for leaks.