1999 Pontiac Montana Owner's Manual - Page 282

yellowblue Overheated Engine Protection Operating Mode This emergency operating mode allows your vehicle to be driven to a safe place in an emergency situation. Should an overheated engine condition exist, an overheat protection mode which alternates firing groups of three cylinders helps prevent engine damage. In this mode, you will notice a significant loss in power and engine performance. The low coolant light may come on and the temperature gage will indicate an overheat condition exists. Towing a trailer in the overheat protection mode should be avoided. If Steam Is Coming From Your Engine NOTICE: After driving in the overheated engine protection operating mode, to avoid engine damage, allow the engine to cool before attempting any repair. The engine oil will be severely degraded. Repair the cause of coolant loss and change the oil. See "Engine Oil" in the Index. 5-10