The cylinder head supplied as a spare part can be used on either the left or right side. In this case, the plug in the end of the head must be located on the front side of the head (see fig. 2.51). When installing the plug, apply AMW 188 001 02 sealant to the outer circumference of the plug. Install the plug flush with the end of the cylinder head.
Remove the air pipe connecting the intake pipe and the air flow meter:
Unscrew the fuel line, remove it together with the injectors and, without disconnecting the hoses, move it to the side.
Unscrew the bolt securing the engine oil dipstick guide pipe to the cylinder head and pull the pipe upward.
Unscrew and remove the ignition coils together with the holders.
Unscrew the intake pipe channel switching valve from the cylinder head.
Remove the timing belt and camshaft pulley.
Unscrew the rear timing belt cover.
Remove the crankcase ventilation hose.
Supercharged engine: Disconnect the boost pipe from the combination valve in the cylinder head cover.
Unscrew the coolant pipe from the cylinder block.
Unscrew the power steering pump pressure line from the cylinder head cover.
Loosen the cylinder head mounting bolts in sequence from 1 to 8, first by half a turn, then completely unscrew (see fig. 2.52).
Using a metal ruler and feeler gauge, check the flatness of the mating surfaces. The deviation from flatness should be no more than 0.1 mm.
If there are small defects on the mating surface of the cylinder head, they can be removed by mechanical processing.
The height of the cylinder head after machining should be 139.25 mm.
When installing the cylinder head, a new gasket must be used. Remove the gasket from its sealed packaging immediately before installing it on the cylinder block. Check that the new cylinder head gasket is the same type as the original and that the TOP or OBEN marking is facing upwards.
Gradually tighten the cylinder head mounting bolts in several stages in the sequence shown in Fig. 2.52.
Step 1 - Tighten to 60 Nm;
Step 2 - Turn to 90°;
Step 3 - Turn to 90°
Before installing the inner cylinder head cover gasket, lubricate the transitions (including on the opposite side) from the bearing caps to the cylinder head with Loctite Ultra Black or AUDI AMV17400401. Install the cylinder head cover gasket.
First tighten the inner cylinder head cover nuts to 10 Nm, then the outer nuts to the same torque.