2002 Mercury Grand Marquis Owner Guide 1st Printing - Page 11

Instrument Cluster Check engine Illuminates briefly to ensure the system is functional. If it comes on CHECK after the engine is started, one of ENGINE the engine's emission control systems may be malfunctioning. The light may illuminate without a driveability concern being noted and will not require towing. Light turns on solid: Temporary malfunctions may cause your light to illuminate. Examples are: 1. The vehicle has run out of fuel. 2. Poor fuel quality or water in the fuel. 3. The fuel cap may not have been properly installed and securely tightened. These temporary malfunctions can be corrected by filling the fuel tank with high quality fuel of the recommended octane and/or properly installing and securely tightening the fuel cap. After three driving cycles without these or any other temporary malfunctions present, the light should turn off. (A driving cycle consists of a cold engine startup followed by mixed city/highway driving.) No additional vehicle service is required. If the light remains on, have your vehicle serviced at the first available opportunity. Light is blinking: Engine misfire is occurring which could damage your catalytic converter. You should drive in a moderate fashion (avoid heavy acceleration and deceleration) and have your vehicle serviced at the first available opportunity. Under engine misfire conditions, excessive exhaust temperatures could damage the catalytic converter, the fuel system, interior floor coverings or other vehicle components, possibly causing a fire. 11