TO No.41
Audi recommends replacing the air filter element every 30,000 km. Under normal operating conditions, this interval is quite sufficient; moreover, if you clean the replaceable element between replacements. However, when driving on dirt roads, you need to think about replacement much earlier, despite the more frequent cleaning of the replaceable element. Removal and installation, see the previous text.
(The full version is posted on the resource «AUDIMANUAL»)