Buick LaCrosse Owner's Manual page 352

To inspect or replace the engine air
cleaner/filter:
1. Remove the six screws on top of
the engine air cleaner/filter
housing.
2. Lift the filter cover housing away
from the engine air cleaner/filter
housing.
3. Pull out the filter.
4. Inspect or replace the engine air
cleaner/filter.
5. Lower the filter cover housing
toward the engine.
6. Install the six screws on the top
of the housing to lock the cover
in place.
1. Remove the screws on top of
the engine air cleaner/filter
housing.
2. Lift the filter cover housing away
from the engine.
3. Pull out the filter.
4. Inspect or replace the engine air
cleaner/filter.
5. Lower the filter cover housing
toward the engine.
6. Install the screws on the top of
the housing to lock the cover in
place.
Operating the engine with the air
cleaner/filter off can cause you or
others to be burned. The air
cleaner not only cleans the air; it
helps to stop flames if the engine
backfires. Use caution when
working on the engine and do not
drive with the air cleaner/filter off.