2008 Chevrolet Impala Owner's Manual - Page 276

If Steam Is Coming From Your Engine If No Steam Is Coming From Your Engine An overheat warning can indicate a serious problem. If you get an engine overheat warning but see or hear no steam, the problem may not be too serious. Sometimes the engine can get a little too hot when you: {CAUTION: 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. 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 open the hood. If you keep driving when the vehicles engine is overheated, the liquids in it can catch fire. You or others could be badly burned. Stop your engine if it overheats, and get out of the vehicle until the engine is cool. See Overheated Engine Protection Operating Mode on page 5-31 for information on driving to a safe place in an emergency. Notice: If your engine catches fire because you keep driving with no coolant, your vehicle can be badly damaged. The costly repairs would not be covered by your warranty. See Overheated Engine Protection Operating Mode on page 5-31 for information on driving to a safe place in an emergency. 5-30 Climb a long hill on a hot day. Stop after high-speed driving. Idle for long periods in traffic. Tow a trailer. If an overheat warning occurs without any sign of steam, try this for a minute or so: 1. In heavy traffic, let the engine idle in NEUTRAL (N) while stopped. If it is safe to do so, pull off the road, shift to PARK (P) or NEUTRAL (N) and let the engine idle. 2. Set the heater at the highest setting and the fan at the highest speed and open the windows as necessary.