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Emission Control Systems: Description and Operation

This vehicle is equipped with a vehicle emission control information label. The label is affixed to the engine or the engine compartment. The information on this label includes: label code, model year, certification standards (Federal, California or both), engine family, engine size, engine tune up adjustment and specifications, applicable emission control components or systems and in some cases the emission control system vacuum hose routing. Some manufacturers will affix a separate emission vacuum hoses routing label to the engine compartment. If a modification to the vehicle emission control system has been authorized by the vehicle manufacturer, an Emission Control Modification Label should be affixed to the engine compartment noting this change.

California BAR (Bureau Of Automotive Repair) and other state emission control inspection and maintenance laws, may require an additional certification label to be affixed to the vehicle. These labels may be required on kit vehicles, gray market vehicles or vehicles in which an approved modification or component change may have been performed.