HRS §291-24.5
Rules for quiet mufflers on public roads
This law bans using, selling, altering, or installing mufflers that make a vehicle noticeably louder than it was from the factory. Police can enforce it, and violators face fines that increase for repeat offenses within three years.
everyone
The statute, as written — Motor vehicle muffler
(a) No person shall use on a public highway, sell, offer for sale, alter, or install a muffler, including but not limited to a cut-out, bypass, or similar device, that will noticeably increase the noise emitted by a motor vehicle above that emitted by the vehicle as equipped from the factory. (b) Except as provided in section 291-24.4, any violation of this section shall be enforceable by police officers. Violation of this section shall subject the violator to the following penalties: (1) For a first violation, or any violation not preceded within a three-year period for a violation under this section, the person shall be fined not more than $150; (2) For a second violation committed within three years of any other violation under this section, the person shall be fined not more than $350; and (3) For a violation of a third or subsequent offense committed within three years of any other violation under this section, the person shall be fined not more than $950. Any person who violates the provisions of this section may be issued a summons or citation for the violation.
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