GMC 2009 Sierra - Manual (Page 330)

How to Inspect the Engine
Air Cleaner/Filter
Vehicles With an Air Filter
Restriction Indicator
Locate the air filter restriction indicator on the engine
air cleaner/filter cover. When the indicator turns black
or is in the red/orange “change” zone, replace the
filter and reset the indicator. See the steps following
to replace the engine air cleaner/filter and to reset
the air filter restriction indicator.
Vehicles Without an Air Filter
Restriction Indicator
To inspect the air cleaner/filter, remove the engine
air cleaner/filter from the vehicle by following Steps 1
through 6. When you have the engine air cleaner/filter
removed, lightly shake it to release loose dust and
dirt. If the engine air cleaner/filter remains caked
with dirt, a new filter is required.
Replacing the Engine Air Cleaner/Filter
and Resetting the Air Filter
Restriction Indicator
1. Locate the air cleaner/
filter assembly.
See Engine
Compartment
Overview
on page 5-12.
2. Loosen the four screws on the cover of the housing
and lift up the cover.
5-18