1994 GMC Sonoma Owner's Manual - Page 72

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. I A CAUTION: Idling the engine withthe air system control off could allow dmgerous exhaust into your vehicle (seethe earlier Caution under "Engine Exhaust"). Also, idling ina closed-in place can let deadly carbon monoxide (CO) into your vehicle evenif the fan switch isat 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'9 the in Index.) ~ A CAUTION: It can be dangerous to get out of your vehicle if the shift lever is not fully in "P" (Park) 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. Youor others could beinjured. To be sure your vehicle won't move, even when you're onfairly level ground, always set your parking brakeand move the shift lever to "P" (Park). If you have four-wheel drive with a manual transfer case shift lever and your transfer case is in "N" (Neutral), your vehicle will be free to roll, even if your shift lever is in " P ' (Park). So, be sure the transfer case is in a drive gear - not in "N" (Neutral). Follow the proper steps to be sure your vehicle won't move. See "Shifting Into 'P' (Park)" in the Index. If you're pulling a trailer, see "Towing a Trailer" in the Index. 2-26