GMC 1995 Suburban Owner's Manual page 104

Running Your Engine While You're Parked
(Automatic Transmission)
It's better not to park
with the engine running.
But if you ever have to, here
are some things to know.
A
CAUTION:
Idling the engine with the air system control off could allow
dangerous exhaust into your vehicle (see the earlier Caution
under "Engine Exhaust").
Also, idling in
a
closed-in place can let deadly carbon monoxide
(CO) into your vehicle even if the fan switch is at the highest
setting. One place this can happen is a garage. Exhaust
-
with
CO
-
can come in easily. NEVER park in a garage with the
engine running.
Another closed-in place can be
a
blizzard. (See "Blizzard" in the
Index.)
A
CAUTION:
I t can be dangerous to get out of your vehicle if the shift lever is
not fully in PARK
(P)
with the parking brake firmly set. Your
vehicle can roll. Don't leave your vehicle when the engine is
running unless you have to.
If
you've left the engine running, the
vehicle can move suddenly. You or others could be injured. To be
sure your vehicle won't move, even when you're on fairly level
ground, always set your parking brake and move the shift lever
to PARK (P).
If you have four-wheel drive and your transfer case is i n NEUTRAL (N),
your vehicle will be free to roll, even if your
shift
lever is i n PARK (P). So,
be sure the transfer case is in
a
drive gear
-
not
i n
NEUTRAL (N). Always
set your parking brake. Follow the proper steps
t o
be sure your vehicle
won't move. See "Shifting Into PARK (P)" i n the Index.
I f you're pulling a trailer. see "Towing
a
Trailer" i n the Index.
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