Wylie, TX Noise Ordinances: Vehicle Noise (2026)

Wylie Code of Ordinances § 110-19 sets the city's baseline muffler rule inside Chapter 110, Article I, the general traffic provisions enforced by the Wylie Police Department. Every motor vehicle operating in the city must, at all times, carry a muffler in good working condition and in constant operation so it prevents excessive or unusual noise and smoke that would annoy a reasonable, prudent person, and the section separately bars anyone from using a muffler cutout, bypass or similar device on a motor vehicle in the city, a rule aimed squarely at aftermarket exhaust modifications that let engine noise escape unmuffled.

The very next section, § 110-20, backs this up by requiring that a vehicle's engine and power mechanism be equipped and adjusted to prevent the escape of excessive fumes or smoke, so a car that is loud from a cut exhaust and a car that is smoking from a poorly tuned engine are both reachable under this pair of sections. The code's own footnote to § 110-19 points to the state's parallel muffler requirement in Texas Transportation Code § 547.604, which the city provision supplements rather than replaces; an officer can cite under the city ordinance without having to prove a separate state offense.

Neither § 110-19 nor § 110-20 states its own fine, so a violation of either is a Chapter 110 traffic offense punished under the citywide general penalty at Wylie Code of Ordinances § 1-13, which caps most traffic-law violations as a Class C misdemeanor at a fine not to exceed $200.00, with no penalty allowed to exceed what state law sets for the same or a similar offense. There is no separate registration, permit or decibel-meter test named in the ordinance; the standard the police apply is whether the noise or smoke would annoy a reasonable, prudent person, which leaves the call to the officer's judgment at a traffic stop.