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Regulations for Emissions from Vehicles and Engines

Final Rule for Control of Air Pollution From Motor Vehicles and New Motor Vehicle Engines; Modification of Federal Onboard Diagnostic Regulations for Light-Duty Vehicles and Light-Duty Trucks; Extension of Acceptance of California OBD

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Rule Summary

This action finalizes modifications to the federal on-board diagnostics regulations, including: harmonizing the emission levels above which a component or system is considered malfunctioning with those of the California Air Resources Board (CARB) OBD II requirements; mandating that EPA OBD systems fully evaluate the entire emission control system, including the evaporative emission control system; indefinitely extending the allowance of deficiencies for federal OBD vehicles; indefinitely extending the allowance of optional compliance with the California OBD II requirements for federal OBD certification while also updating the allowed version of those California OBD II regulations to the most recently published version.

Regulations for Emissions from Vehicles and Engines Home