2003 Chevrolet Impala Owner's Manual - Page 282

Radiator Pressure Cap Notice: Your radiator cap is a pressure-type cap and must be tightly installedto prevent coolant loss and possible engine damage from overheating. Be sure the arrows on the cap line with the up overflow tube on the radiator filler neck. The radiator pressure cap is located in the front of the engine compartment on the passenger's side, near the diagonal cross brace. 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 low coolant light may come on and 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 wiil find a cooiant temperature gage and a warning message about a hot engine on your instrument panel cluster. See Engine Coolant Temperature Gage on page 3-35 and Hot Coolant Temperature Warning Message on page 3-41. 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" in the Index. 5-29