GMC 2011 Sierra - Manual (Page 338)

Black plate (44,1) GMC Sierra Owner Manual - 2011
9-44 Driving and Operating
Active Fuel Management
®
Vehicles with V8 engines may
have Active Fuel Management™.
This system allows the engine to
operate on either all or half of its
cylinders, depending on the driving
conditions.
When less power is required, such
as cruising at a constant vehicle
speed, the system will operate in
the half cylinder mode, allowing
the vehicle to achieve better fuel
economy. When greater power
demands are required, such as
accelerating from a stop, passing,
or merging onto a freeway, the
system will maintain full-cylinder
operation.
If the vehicle has an Active
Fuel Management™ indicator, see
Driver Information Center (DIC) on
page 5‑33 for more information on
using this display.
Engine Exhaust
{
WARNING
Engine exhaust contains Carbon
Monoxide (CO) which cannot be
seen or smelled. Exposure to CO
can cause unconsciousness and
even death.
Exhaust may enter the vehicle if:
. The vehicle idles in areas
with poor ventilation (parking
garages, tunnels, deep snow
that may block underbody
airflow or tail pipes).
. The exhaust smells or
sounds strange or different.
. The exhaust system leaks
due to corrosion or damage.
. The vehicle exhaust system
has been modified, damaged
or improperly repaired.
(Continued)
WARNING (Continued)
. There are holes or openings
in the vehicle body from
damage or after-market
modifications that are not
completely sealed.
If unusual fumes are detected or
if it is suspected that exhaust is
coming into the vehicle:
. Drive it only with the windows
completely down.
. Have the vehicle repaired
immediately.
Never park the vehicle with the
engine running in an enclosed
area such as a garage or a
building that has no fresh air
ventilation.