Active Fuel Management; Extended Parking; Engine Exhaust - GMC YUKON 2017 Owner's Manual

226 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) 0 152 for
more information on using this
display.
®

Extended Parking

It is better not to park with the
vehicle running. If the vehicle is left
while running, follow the proper
steps to be sure the vehicle will not
move and there is adequate
ventilation. See Shifting Into Park
0 224 and Engine Exhaust 0 226.
If the vehicle is left in P (Park) while
running and the Remote Keyless
Entry (RKE) transmitter is outside
the vehicle, the vehicle will turn off
after one hour.
If the vehicle is left in P (Park) while
running and the RKE transmitter is
inside, the vehicle will run for two
hours. At the end of the second
hour, the vehicle will turn off.
The timer will reset if the vehicle is
taken out of P (Park) while it is
running.

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.
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