Bishop, CA Noise Ordinances: Vehicle Noise (2026)

California preempts most vehicle-noise regulation through the Vehicle Code, so Inyo County does not set its own decibel limits for cars and motorcycles. Vehicle Code 27150 requires every motor vehicle to be equipped with an adequate muffler in constant operation and properly maintained to prevent excessive or unusual noise, and forbids muffler cutouts or bypasses. Vehicle Code 27151 makes it unlawful to modify an exhaust system to amplify or increase vehicle noise beyond what 27150 and the Article 2.5 noise limits allow. Vehicle Code 23130 sets maximum noise levels for vehicles in actual use on the highway. These statutes are enforced by the Inyo County Sheriff's Office and the California Highway Patrol throughout the county, including along US-395 and SR-190 corridors near Lone Pine, Independence and Olancha. The County Code adds one local touchpoint: in county parks, Section 12.16.110 prohibits disturbing the peace by blowing automobile horns or using other noise-making devices. General-nuisance authority (Title 22) and Penal Code 415 can also apply to a vehicle creating a sustained disturbance off the roadway, such as a parked car with a loud stereo.