Diesel Truck Liberation Act of 2025

This bill prohibits the enforcement of federal laws requiring emissions control devices or onboard diagnostic systems on motor vehicles and engines, repeals related regulations, and eliminates liability for noncompliance. Sec. 2, Prohibition on enforcement of emissions control device laws: No federal law may require manufacturers, importers, or distributors to install, certify, or maintain emissions control devices or onboard diagnostic systems on any motor vehicle or engine. The EPA Administrator cannot enforce any such requirements under the Clean Air Act or other federal laws. No person or entity faces civil or criminal liability for manufacturing, selling, importing, purchasing, using, or modifying vehicles or engines without these devices. All existing regulations on installation, modification, or removal of emissions controls are void. Any criminal imprisonment penalties for related conduct are vacated, and records of findings for such liability are expunged.