2004 Buick Century Owner's Manual - Page 230

Engine Air Cleaner/Filter See Engine Compartment Overview on page 5-12 for location of engine air cleaner/filter. 2. Lift the two clips located on the top of the filter assembly to unlock the cover. When to Inspect the Engine Air Cleaner/Filter Inspect the air cleaner/filter at every oil change and replace at the first oil change after 25,000 miles (40 000 km). How to Inspect the Engine Air Cleaner/Filter To inspect the air cleaner/filter remove it from the vehicle and lightly shake the filter to release loose dust and dirt. If the filter remains caked with dirt, a new filter is required. To check or replace the engine air cleaner/filter, do the following: 1. Loosen the screw and clamp on the air duct. 3. Disconnect the duct and reposition it while removing the cover. 4. Pull out the filter. 5. Inspect or replace the filter if needed. 6. Reinstall the filter. 7. Push the two clips located on top of the filter assembly to lock the cover. 5-18