Buick 2004 Century - Manual (Page 230)

Engine Air Cleaner/Filter
See Engine Compartment Overview on page 5-12 for
location of engine air cleaner/filter.
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.
2. Lift the two clips
located on the top of
the filter assembly
to unlock the cover.
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.
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