GMC 1996 Sierra Owner's Manual page 92

Engine Exhaust
I
A
CAUTION:
-
Engine exhaust can kill. It contains the gas
carbon monoxide (CO), which you can't see or
smell. It can cause unconsciousness and death.
You might have exhaust coming in if:
Your exhaust system sounds strange or different.
Your vehicle gets rusty underneath.
Your vehicle was damaged in a collision.
Your vehicle was damaged when driving over
high points on the road or over road debris.
Repairs weren't done correctly.
Your vehicle or exhaust system had been
If you ever suspect exhaust is coming into
your vehicle:
Drive it only with all the windows down to
Have your vehicle fixed immediately.
modified improperly.
blow out any CO; and
I
Zunning Your Engine While You're
larked (Automatic Transmission)
It's better not to park with the engine running. But if you
ever have to, here are some things to know.
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.)
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