Have you recently changed brands of fuel?If so, be sure to fuel your vehicle with quality fuel.SeeGasoline Octane on page 5-4. 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 has theproper test equipment and diagnostic tools to fix anymechanical or electrical problems that may havedeveloped.Emissions Inspection andMaintenance ProgramsSome 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 theCheck Engine light is on or not working properly.Your vehicle will not pass this inspection if theOBD (on-board diagnostic) system determines thatcritical emission control systems have not beencompletely diagnosed by the system. The vehiclewould be considered not ready for inspection.This can happen if you have recently replaced yourbattery or if your battery has run down. The diagnosticsystem is designed to evaluate critical emissioncontrol systems during normal driving. This may takeseveral days of routine driving. If you have done this andyour vehicle still does not pass the inspection for lackof OBD system readiness, your GM dealer can preparethe vehicle for inspection.3-45
