1998 GMC Envoy Owner's Manual - Page 222

Engine Overheating You will find a coolant temperature gage on your vehicle's instrument panel. See "Gages" in the Index. A CAUTION: If Steam Is Coming From Your Engine Steam from a n overheated engine can burn you away badly, even if you ,justopen the hood. Stay from the engine you see or hear steam coming if from it. Just turn it and get everyone away off from the vehicle until it cools down. Wait until there is no signof steam or coolant before you open the hood. If you keep driving when your engine is overheated, the liquids in it can catch You o r fire. others could be badly burned. Stop your engine if it overheats, and get out the vehicle until the of engine is cool. NOTICE: If your engine catches fire because keep you driving with no coolant, your vehicle can be badly damaged. The costly repairswould not be covered by your warranty. 5-11