1997 Chevrolet Lumina Owner's Manual - Page 129

Malfunction Indicator Lamp (Service Engine Soon Light) Your Chevrolet is equipped with acomputer which monitors operationof the fuel, ignition andemission control systems. I NOTICE: If you keep driving your vehicle with this light on, after a while, your emission controls may not work as well, your fuel economy may not be as good and your engine may not run as smoothly. This could lead to costly repairs that may not be covered by your warranty. SERVICE ENGINE SOON This system is called OBDI1 (On-Board Diagnostics-Second Generation) and is intended to assure thatemissions are at acceptable levels the life for of the vehicle, helping to produce a cleaner environment. (In Canada, OBD I1 is replaced by Enhanced Diagnostics.) The SERVICE ENGINE SOON light comes on to indicate that there a problem and is service is required. Malfunctions often will be indicated by the system before any problem is apparent. This may prevent more serious damage to your vehicle. This system is also designed to assist your service technician in correctly diagnosing any malfunction. This light shouldcome on, as acheck to show youit is working, whenthe ignition is on and engine is not the running. If the light doesn't come on, have it repaired. This light will also come on during a malfunctionin one of two ways: 0 0 Light Flashing -- A misfire condition has been detected. A misfire increases vehicle emissions and may damage the emission control system on your vehicle. Dealer or qualified service center diagnosis and service is required. Light On Steady -- An emission control system malfunction has been detected on your vehicle. Dealer or qualified service center diagnosis and service may be required. 2-55