1998 Chevrolet Express Van Owner's Manual - Page 214

If No Steam Is Coming From Your Engine If you get the overheat warning but see orhear no steam, the problem may not be too serious. Sometimes the engine can get little too hot when you: a Climb a long hill on a hot day. Stop after high-speed driving. Idle for long periods in traffic. Tow a trailer. See "Driving on Grades" in the Index. If you get the overheat warning with no sign of steam, try this for a minute or so: If you no longer have the overheat warning, you can drive. Just to be safe, drive slower for about 10 minutes. If the warning doesn't come back on, you can drive normally. If the warning contikties, pull over,stop, and park your vehicle right away. If there's stillno sign of steam, push the accelerator until the engine speed is about twice as fast asnormal idle speed. Bring the engine speed back to normal idle speed after two or three minutes. Now see if the warning stops. But then, ifyou still have the warning, turn ofSthe engine and get everyoneout of the vehicle until it cools down. You may decide not to lift the hood but to get service help right away. 1. If you have an air conditioner, turn it off. 2. Turn on your heater to full hot at the highest fan speed and open the window as necessary. 3. If you're in a traffic jam, shift to NEUTRAL (N); otherwise, shift to the highest gear while driving -- DRIVE (D). 5-13