9.24.030 Vehicular noise.
   A.   It shall be unlawful for any person within any residential area of the city to repair, rebuild or test any motor vehicle between the hours of 9:00 p.m. and 6:00 a.m. in such a manner as to create any excessive, unnecessary or offensive noise, such that a reasonable person or normal sensitivity residing in the area is caused discomfort or annoyance.
   B.   No person shall operate, or cause to be operated, any motor vehicle within the city unless the exhaust system of such vehicle:
   1.   Is free from defects which may cause sound level magnification;
   2.   Is equipped with a functioning muffler;
   3.   Has not been modified in such a manner which will amplify or increase the sound level emitted by the motor vehicle above that emitted by a muffler originally installed on the vehicle as manufactured for initial sale.
   C.   The use of any and all exhaust brakes, engine brakes, engine retarders, or similar devices shall be prohibited within the city; provided, however, that it shall be an affirmative defense to a violation of this paragraph that such device was used by the operator as a result of a bona fide emergency, and was reasonably necessary for the protection of persons and/or property.
(Ord. 1397.09.04 § 1 (part), 2006)