Avondale, AZ Noise Ordinances: Vehicle Noise (2026)

Section 15-11(c) lists specific acts the city treats as loud, disturbing, and unnecessary noise, and paragraph (5), 'Exhaust modifications,' targets vehicles directly: it is unlawful to operate or cause to operate a motor vehicle with an exhaust system that contains defects causing sound level magnification, that is not equipped with a muffler at all, or that has been modified so it amplifies or increases the sound level emitted by the motor above what the vehicle's originally manufactured muffler produced. The baseline for comparison is the vehicle 'as manufactured for initial sale,' so an aftermarket exhaust that measurably increases sound output above the factory setup falls within the ban even if the driver never removed the muffler outright.

This sits inside the same section 15-11 that opens by declaring any unreasonably loud, disturbing, and unnecessary noise within city limits a misdemeanor, and any noise detrimental to life, health, or the public peace a separate misdemeanor. Unlike the pet-noise provision in the same section, exhaust-modification violations carry no requirement for two independent written complaints before the city can act; an Avondale police officer or other authorized officer can act directly on observed evidence. The exhaust rule is distinct from, and enforced separately from, the numeric decibel limit table in subsection (c)(7), which measures overall vehicle noise output at fifty feet regardless of whether the exhaust itself is defective or modified.