Monterey Park, CA Noise Ordinances: Vehicle Noise (2026)

Chapter 4.50 generally exempts sound from motor vehicles, trucks, buses, aircraft and trains operating on streets and highways from the city's noise disturbance rules (Section 4.50.050(a)). That exemption has two carve-outs. First, a vehicle idling with attached equipment running, such as a refrigeration or heating unit, for more than ten minutes in any hour while stationary for reasons other than traffic congestion loses the exemption (Section 4.50.050(a)(1)). Second, and more directly aimed at loud stereos, no one may drive or otherwise use a vehicle equipped with sound-amplifying equipment or any other device for producing or reproducing sound on a public street if that sound carries onto private property or is heard by others on the street and exceeds the noise level limits set elsewhere in the chapter (Section 4.50.050(a)(2)).

Those underlying limits are the same land-use-based dBA ceilings in Section 4.50.080, so a car stereo audible above the 50 to 70 dBA range that applies to the receiving property is enforceable. The exemption's carve-outs sit apart from the code's separate vehicle exemptions for automobile radios regulated by the Vehicle Code, emergency vehicle warning devices, and horns used for traffic safety, none of which are affected by this section (Section 4.50.020). The City Planner administers noise enforcement citywide, and the same nighttime and daytime ambient standards used for stationary sources apply to a moving vehicle's amplified sound once it reaches a residential receiving property.