This bill seeks to significantly alter the Clean Air Act by eliminating specific provisions related to state-level emission standards. It repeals Section 209(b), which currently grants California a waiver to set its own motor vehicle emission standards that are more stringent than federal requirements. Additionally, the bill eliminates Section 177, which allows other states to adopt California's emission standards for new motor vehicles and engines. Upon enactment, all previously issued waivers under Section 209(b) would immediately lose their force and effect, and any pending waiver applications would be denied. Furthermore, the legislation introduces a new prohibition, preventing any state or political subdivision from adopting or enforcing emission standards for nonroad engines or vehicles , including those used in construction, agriculture, and locomotives. These changes aim to standardize emission regulations across the nation by removing California's unique regulatory authority and preventing other states from following suit.