Note: Some engines have a snow screen in the air intake. This screen should be removed and cleaned. The air intake should also be free of leaves and other debris.
1. Remove the screws (arrows in illustration 5.12 Chapter 2) and remove the air intake (2). On 3.0 and 4.2 L petrol models, separate the EVAP canister purge valve (1) from the air cleaner.
2. On 1.9 and 2.0 L diesel models, remove the bolts (1 in the illustration), pull the air cleaner cover out of the holder and tilt it towards the engine. On 2.0 TFSI petrol models, you must first disconnect the air flow meter connector and disconnect the hose leading to the turbocharger.
16.2. Screws (1) for securing the air cleaner cover for 1.9 and 2.0 l diesel models and 2.0 TFSI petrol models
3. On 1.6L petrol models, disconnect the outlet hose by loosening the clamp (4 in the illustration), and disconnect the air flow meter connector (3). Then unscrew the bolts (1) and remove the air cleaner cover.
16.3. Fastener (2) of the air cleaner cover, clamp (4) and connector (3) of the air flow meter of 1.6 l petrol models
4. On 1.8L petrol models, loosen the lock (1 in the illustration) and disconnect the canister purge line from the EVAP valve. Disconnect the line (3), remove the two bolts (2), release the air cleaner cover from the clips and move it toward the engine.
16.4. Fastener (2) for air cleaner cover, retainer (1) for EVAP line and line (3) for 1.8L petrol models
5. On 2.5L and 3.0L diesel models and 3.0L petrol models, disconnect the outlet hose by loosening the clamp (4 in the illustration), and disconnect the air flow meter connector (3). Disconnect the hose (1), unscrew the bolts (2), and remove the air cleaner cover. On gasoline models, first separate the two fuel lines from the holder on the air cleaner.
16.5. Fasteners (2) for the air cleaner cover, clamps (4 and 1) for the hoses and connector (3) for the air flow meter for 2.5 and 3.0 l diesel models, as well as 3.0 l petrol models
6. On 3.2L petrol models, remove the retainers (4 in the illustration) and disconnect the hose from the air cleaner. Loosen the clamp and disconnect the hose (1), release the fuel line from the holder (3). Unscrew the two bolts (2) and remove the air cleaner cover.
16.6. Installation details of the air cleaner cover for 3.2L petrol models
7. On 4.2L (S4) petrol models, disconnect the outlet hose by loosening the clamp (4 in the illustration), and disconnect the air flow meter connector (3). Disconnect the hose (1), unscrew the bolts (2), and separate the two fuel lines from the air cleaner. Remove the air cleaner cover by releasing it from the clips.
8. Remove the old filter element from the air cleaner housing, clean the air cleaner housing and install a new filter element. The drain tube in the air cleaner housing should not be clogged.
(The original article is available on the online resource audimanual.ru)