HI SB586

Requires vehicle inspection certificates to include verification that motorcycles, mopeds, and motor vehicles are not equipped with noisy mufflers or exhaust systems that fail to comply with sections 291-24 or 291-24.5.

Directs the Director of Transportation to adopt rules requiring inspections to ensure vehicles do not have non-compliant mufflers or exhaust systems, and suspends, revokes, or refuses renewal of inspection station permits upon a third or subsequent willful violation of such rules within 18 months.

Elevates violations of noisy muffler laws from a fine-only offense to a petty misdemeanor punishable by a fine of up to $500 or imprisonment for up to 30 days.

Expands the definition of prohibited muffler modifications to include cut-outs, bypasses, and similar devices, and adds "offer for sale" to prohibited activities.

Designates repairing or installing non-compliant mufflers or exhaust systems as a prohibited practice subject to motor vehicle repair licensing enforcement.

Effective date: July 1, 2050.