Idaho Exhaust & Muffler Laws (2026)

Info: Your vehicle needs a muffler in good order.

InfoVerified Jun 19, 2026

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Your vehicle needs a muffler in good order. Cutouts and bypasses (which route exhaust around the muffler) are banned, along with changes that make the exhaust louder. In Idaho, "excessive noise" means more than 92 decibels measured at 20 feet (Idaho Code §§ 49-937, 49-106).

Official source: legislature.idaho.gov →

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