GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-14632286) - 2021 - CRC - 11/19/20
238
Driving and Operating
Extended Parking
It is best not to park with the vehicle
running. If the vehicle is left running, be
sure it will not move and there is adequate
ventilation.
See
and
If the vehicle is left parked and running with
the RKE transmitter outside the vehicle, it
will continue to run for up to half an hour.
If the vehicle is left parked and running with
the RKE transmitter inside the vehicle, it will
continue to run for up to an hour.
The vehicle could turn off sooner if it is
parked on a hill, due to lack of
available fuel.
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.
.
There are holes or openings in the
vehicle body from damage or
aftermarket modifications that are not
completely sealed.
(Continued)
Warning (Continued)
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.
Running the Vehicle While Parked
It is better not to park with the engine
running.
If the vehicle is left with the engine running,
follow the proper steps to be sure the
vehicle will not move. See
and
If parking on a hill and pulling a trailer, see
Driving Characteristics and Towing Tips
.
