Did you just drive through a deep puddle of water?If so, your electrical system may be wet. The conditionwill usually be corrected when the electrical systemdries out. A few driving trips should turn the light off.Have you recently changed brands of fuel?If so, be sure to fuel your vehicle with quality fuel. SeeGasoline Octane on page 5-5. Poor fuel quality willcause your engine not to run as efficiently as designed.You may notice this as stalling after start-up, stallingwhen you put the vehicle into gear, misfiring, hesitationon acceleration, or stumbling on acceleration. (Theseconditions may go away once the engine is warmed up.)This will be detected by the system and cause thelight to turn on.If you experience one or more of these conditions,change the fuel brand you use. It will require at leastone full tank of the proper fuel to turn the light off.If none of the above steps have made the light turn off,your dealer can check the vehicle. Your dealer hasthe proper test equipment and diagnostic tools to fixany mechanical or electrical problems that mayhave developed.Emissions Inspection and MaintenanceProgramsSome state/provincial and local governments have ormay begin programs to inspect the emission controlequipment on your vehicle. Failure to pass thisinspection could prevent you from getting a vehicleregistration.Here are some things you need to know to help yourvehicle pass an inspection:Your vehicle will not pass this inspection if the checkengine light is on or not working properly.Your vehicle will not pass this inspection if the OBD(on-board diagnostic) system determines that criticalemission control systems have not been completelydiagnosed by the system. The vehicle would beconsidered not ready for inspection. This can happen ifyou have recently replaced your battery or if yourbattery has run down. The diagnostic system isdesigned to evaluate critical emission control systemsduring normal driving. This may take several daysof routine driving. If you have done this and your vehiclestill does not pass the inspection for lack of OBDsystem readiness, your GM dealer can prepare thevehicle for inspection.3-44
