The engine heater can provide easier starting and better fuel economy during engine warm-up in cold weather conditions at or below -18°C (0°F). Vehicles with an engine heater should be plugged in at least four hours before starting.

It is shipped from the factory with a tie holding it in place. Use care in removing the tie so that the cord is not damaged.
Check the heater cord for damage. If it is damaged, do not use it. See your dealer for a replacement. Inspect the cord for damage yearly.
Warning
Improper use of the heater cord or an extension cord can damage the cord and may result in overheating and fire.
Failure to use the recommended extension cord in good operating condition, or using a damaged heater or extension cord, could make it overheat and cause a fire, property damage, electric shock, and injury.
Keep the cord away from any moving parts.
If you do not it could be damaged.
The length of time the heater should remain plugged in depends on several factors. Ask a dealer in the area where you will be parking the vehicle for the best advice on this.
Starting the Engine
Retained Accessory Power (RAP)If Steam Is Coming from the Engine Compartment
Warning
Steam from an overheated engine can burn you badly, even if you
just open the hood. Stay away from the engine if you see or hear steam coming from
it. Just turn it off and get everyone away from the vehicle until it cools down.
Wait until there is no sign of steam or coolant before you ...
Reporting Safety Defects to General Motors
In addition to notifying NHTSA (or Transport Canada) in a situation like this,
notify General Motors.
Call 1-800-222-1020, or write: Chevrolet Motor Division
Chevrolet Customer Assistance Center
P.O. Box 33170
Detroit, MI 48232-5170
In Canada, call 1-800-263-3777
(English) or 1-800-263-7854
...
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 a ...