2005 Buick Rendezvous Owner's Manual - Page 350

Overheated Engine Protection Operating Mode This emergency operating mode allows your vehicle to be driven to a safe place in an emergency situation. If an overheated engine condition exists, an overheat protection mode which alternates firing groups of cylinders helps prevent engine damage. In this mode, you will notice a significant loss in power and engine performance. If your vehicle is equipped with the 3.6L V6 engine, the reduced engine power message along with the engine coolant temperature warning message will come on to indicate the vehicle has entered overheated engine protection operating mode. The temperature gage will also indicate an overheat condition exists. Driving extended miles (km) and/or towing a trailer in the overheat protection mode should be avoided. 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, change the oil and reset the oil life system. See Engine Oil on page 5-16. Cooling System When you decide it is safe to lift the hood, here is what you will see: 3400 V6 engine 5-30