CHEVROLET 2009 Impala - Manual (Page 275)

2. Push the filter cover housing toward the engine.
3. Pull out the filter.
4. Inspect or replace the engine air cleaner/filter.
5. To reinstall the cover, position the tabs through the
hinges on the housing.
6. Push the cover tabs on top of the housing to lock
the cover in place.
{ CAUTION:
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. If it is not there and
the engine backfires, you could be burned. Do not
drive with it off, and be careful working on the
engine with the air cleaner/filter off.
Notice: If the air cleaner/filter is off, a backfire can
cause a damaging engine fire. And, dirt can easily get
into the engine, which will damage it. Always have
the air cleaner/filter in place when you are driving.
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