How do you change the air filter on a Citroen C4 grand Picasso?

To change the air filter on a Citroen C4 Grand Picasso, first locate the air filter housing, which is typically situated near the engine. Open the housing by unclipping or unscrewing it, then carefully remove the old air filter. Clean any debris from the housing before inserting the new filter, ensuring it fits snugly. Finally, resecure the housing and check that everything is properly sealed before closing the hood.