Remove the upper sound absorber panel from the engine. For the 225 hp engine (code: AMU, BEA), disconnect hoses and clamps to remove the intake air duct. Seal off openings of the charge air circuit with clean rags to prevent dirt entry. Remove mounting bolts and the vacuum reservoir from the top of the cylinder head cover, tilting it toward the rear to place it out of the way. Disconnect the harness connector for the turbocharger recirculation valve (N249) and remove the mounting bolts to position the bracket for the turbocharger recirculation valve out of the way. Remove the mounting bolts and rear bracket for the intake air duct. Loosen the clamp and remove the breather hose from the cylinder head cover. For the 225 hp engine, loosen the clamps, remove the bolt, and take out the vacuum line for the throttle valve control module. Disconnect the harness connectors and unbolt the ground wire for the ignition coils, prying out the retaining tab to position the ignition coil wiring harness out of the way. Unclip the upper timing belt cover, remove the bolt, and position the bracket out of the way. Remove the screws and heat insulation wrap, then take out the remaining coil mounting bolts and ignition coils, noting the cylinder numbers. Unbolt the cylinder head cover mounting bolts and remove the cylinder head cover. Before installing the cylinder head cover, apply drops of sealant at both corners of the cylinder head sealing surfaces and at the sides of the joints, using Audi sealant. Replace the cylinder head cover gasket if damaged, and tighten the cylinder head cover bolts in a diagonal sequence to the specified torque. The remaining installation follows the reverse order of removal.