1998 Pontiac Firebird Owner's Manual - Page 141

This system is called OBD I1 (On-Board Diagnostics-Second Generation) and intended to is assure that emissions at acceptable levelsfor the life are of the vehicle, helping to produce a cleaner environment. The SERVICE ENGINE SOON light comes on to indicate that there is a problem and service is required.Malfunctions often will be indicated the by system before any problem apparent. This may is prevent more serious damage to your vehicle. This system is also designed to assist your service technician in correctly diagnosing any malfunction. This light should come on, as a to show you it is check working, when the ignition is on and the engine is not running. If the light doesn't come on, have it repaired. This light willalso come on during a malfunction in one of two ways: 0 Light Flashing -- A misfire condition has been detected. A misfiie increases vehicleemissions and may damage the emissioncontrol system on your vehicle. Dealer or qualified servicecenter diagnosis and service may be required. Light On Steady -- An emission control system malfunction has been detected on your vehicle. NOTICE: If you keep driving your vehicle this light with on, after a while, your emission controls may not work as well, your fuel economy not be as may good and your engine may not run as smoothly. This could lead to costly repairs that may not be covered by your warranty. Dealer or qualified service center diagnosis and service maybe required. 2-86