2003 Pontiac Montana Owner's Manual - Page 347

Radiator Pressure Cap Notice: Your radiator cap is a pressure-type cap and must be tightly installed to prevent coolant loss and possible engine damage from overheating. Be sure the arrows on the cap line up with the overflow tube on the radiator filler neck. The radiator pressure cap is located at the front of the engine compartment on the passenger's side of the vehicle. See Engine Compartment Overview on page 5-12 for more information on location. 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. The temperature gage will indicate an overheat condition exists. Driving extended miles (km) and/or towing a trailer in the overheat protection mode should be avoided. Engine Overheating You will find an engine coolant temperature gage on your vehicle's instrument panel cluster. See Engine Coolant Temperature Gageon page 3-42. You also have an engine coolant temperature warning message on your instrument panel. See Engine Coolant Temperature Warning Message on page 3-49. 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 coolantloss, change the oil and reset the oil life system. See "Engine Oil" in the Index. 5-26