Audi Workshop Service and Repair Manuals

Removing and installing cylinder head Special tools and workshop equipment required

t  Engine bung set -VAS 6122- Removing   Note t  Fit cable ties in the original positions when installing. t  All open inlet and exhaust ports must be sealed with suitable plugs (e.g. from engine bung set -VAS 6122-. –  Remove camshafts → Chapter.   Caution Avoid damage to valves and piston crowns. Do not turn the crankshaft after the camshafts have been removed. –  Remove front exhaust pipe/front silencer → Chapter.

–  Pull seal off plenum chamber partition panel. –  Remove plenum chamber cover → Rep. gr.50.

–  Disconnect vacuum hose -3- on rear side of plenum chamber partition panel in direction of -arrow- and detach vacuum connection -2- from plenum chamber partition panel. –  Disconnect coolant hoses on rear of cylinder head.

Caution Protect fuel system against contamination. Rules for cleanliness when working on the injection system → Chapter. –  Disconnect fuel supply hose -1- by pressing release ring. –  Disconnect hose -2- from activated charcoal filter.

–  Open hose clip -1- and detach air hose.

–  Unplug electrical connector -1- for Lambda probe -G39- and Lambda probe heater -Z19- and move wiring clear. –  Unplug electrical connector -4- for Lambda probe after catalytic converter -G130- and Lambda probe 1 heater after catalytic converter -Z29- and move wiring clear.

–  Remove nuts -1- from above push catalytic converter towards rear.

–  Remove heat shield -arrows-.

–  Remove nuts -arrows-.

–  Pull turbocharger off studs in direction of -arrow-.

–  Unplug electrical connector -1- for charge pressure sender -G31- and move clear. –  Open hose clip -2- and detach air hose.

–  Unplug the following electrical connectors: 2 -  From knock sensor 1 -G61- (unplug and move clear). 3 -  From intake manifold flap valve -N316-, fuel pressure sender -G247- and Hall sender -G40- 4 -  From injectors 5 -  From throttle valve module -J338- 6 -  From intake air temperature sender -G42-

–  Unplug electrical connector -2- and move wiring clear.

–  Unbolt bracket for coolant pipe -arrow-.   Note The installation position is shown in the following illustrations with the engine removed.

–  Remove intake manifold support (remove securing nut -1- and bolt -2-).

–  Open hose clip -arrow-, detach air hose and swivel to side.

–  Unplug electrical connectors -1 and 3- from oil pressure switch -F22- and oil pressure switch for reduced oil pressure -F378-. –  Remove spark plugs with spark plug spanner -3122 B-.

–  Remove bolts -arrows-. –  Remove cylinder head bolts in the sequence -1 ... 10-.   Note t  Make sure all hoses/pipes and wiring on component are removed. t  Make sure tensioning rail and guide rail are not damaged when lifting off cylinder head. –  Take off cylinder head. –  Place cylinder head onto soft surface (foam plastic). Installing l  Tightening torques → Chapter „Removing and installing cylinder head“   Caution Avoid damage to sealing surfaces. t  Carefully remove sealant residue from cylinder head and cylinder block. t  Ensure that no long scores or scratches are made on the surfaces. Avoid damage to cylinder block. No oil or coolant must be allowed to remain in the blind holes for the cylinder head bolts in the cylinder block. Ensure that cylinder head gasket seals properly: t  Carefully remove any remaining emery and abrasive material. t  Do not remove new cylinder head gasket from packaging until it is ready to be fitted. t  Handle the cylinder head gasket very carefully to prevent damage to the silicone coating or the indented area of the gasket. Avoid damage to open valves. When installing an exchange cylinder head, the plastic protectors fitted to protect the open valves should not be removed until the cylinder head is ready to be fitted. Avoid damage to valves and piston crowns after working on valve gear. Turn the engine carefully at least 2 rotations to ensure that none of the valves make contact when the starter is operated.   Note t  Renew the bolts tightened with specified tightening angle. t  Renew seals, gaskets and self-locking nuts. t  Note the different sealants for sealing surfaces and cylinder head bolts. t  When installing an exchange cylinder head, the contact surfaces between the hydraulic compensation elements, roller rocker fingers and cams must be oiled before installing the camshafts. t  Hose connections and air pipes and hoses must be free of oil and grease before assembly. t  Secure all hose connections with the correct type of hose clips (same as original equipment) → Electronic parts catalogue. t  To ensure that the charge air hoses can be properly secured at their connections, spray rust remover onto the worm thread of used hose clips before installing. t  After fitting a new cylinder head or cylinder head gasket, change the engine oil and coolant.

–  Place cylinder head gasket in position. t  Note position of centring pins in cylinder block -arrows-. t  Note installation position of cylinder head gasket. Part No. should be legible from inlet side.   WARNING Make sure that components are not damaged by the timing chain when rotating the crankshaft. –  If crankshaft has been rotated: set No. 1 cylinder piston to top dead centre and then turn crankshaft back slightly. –  Fit cylinder head. –  Insert and hand-tighten cylinder head bolts. –  Tightening sequence for cylinder head → Fig. „„Tightening sequence for cylinder head““   Note Cylinder head bolts do not have to be torqued down again later after repair work.

–  Turn vibration damper to „TDC“ position -arrow- using counterhold tool -T10355-. l  Notch on vibration damper must align with arrow marking on cover for timing chains (bottom). The remaining installation steps are carried out in the reverse sequence. Note the following points: –  Install camshafts → Chapter. –  Install timing chain cover (top) → Chapter. –  Change engine oil, A4 → Booklet812, A5 → Booklet811. –  Fill cooling system with fresh coolant → Chapter. –  Install catalytic converter → Chapter. –  Install front exhaust pipe/front silencer → Chapter.   WARNING Never use battery charging equipment for boost starting. There is danger of damaging the vehicle's control units.