automobile or light truck— (A) which is treated as a motor vehicle for purposes of title II of the Clean Air Act, (B) which achieves a fuel-economy rating that is less efficient than the reference fuel-economy rating for such motor vehicle for the model year, (C) which has a gross vehicle weight rating of not more than 8,500 pounds, and (D) which is made by a manufacturer beginning with model year 2023. (2) Exception for emergency vehicles The term fuel guzzler motor vehicle does not include any vehicle sold for use and used— (A) as an ambulance or combination ambulance-hearse, (B) by the United States or by a State or local government for police or other law enforcement purposes, or (C) for other emergency uses prescribed by the Secretary by regulations. (c) Other definitions For purposes of this section— (1) Fuel-economy rating The term fuel-economy rating means, with respect to any motor vehicle, the combined fuel-economy rating for such motor vehicle, expressed in gallons per mile, determined in accordance with section 32904 of title 49, United States Code. (2) Model year The term model year has the meaning given such term under section 32901(a) of such title 49. (3) Motor vehicle The term motor vehicle means any vehicle which is manufactured primarily for use on public streets, roads, and highways (not including a vehicle operated exclusively on a rail or rails) and which has at least 4 wheels. (4) Reference fuel-economy rating The term reference fuel-economy rating means, with respect to any motor vehicle, the fuel economy standard for such motor vehicle, expressed in gallons per mile, calculated by applying the relevant vehicle attributes to the mathematical function published pursuant to section 32902(b)(3)(A) of title 49, United States Code. (5) Other terms The terms automobile , passenger automobile , light truck , and manufacturer have the meanings given such terms in regulations prescribed by the Administrator of the Environmental Protection Agency for purposes of the administration of title II of