EXCESSIVE NOISE ENFORCEMENT PASSENGER VEHICLES, LIGHT TRUCKS AND MOTORCYCLES The California Highway Patrol (CHP), Commercial Vehicle Section (CVS), has received many inquiries about excessive noise emitted by passenger vehicles, light trucks and motorcycles. Enforcement personnel and the public have inquired regarding enforcement of the Vehicle Code (VC) sections pertaining to excessive noise emitted by these vehicles. Excessive noise is primarily a nuisance issue rather than a safety concern, and determination of excessive noise is subjective. For this reason, enforcement personnel are to exercise sound professional judgment in making a determination of violation. The following guidelines and attached question and answer sheet (Attachment A) provide guidance to enforcement personnel regarding appropriate enforcement procedures. Enforcement Guidelines The only drivers who should be cited are those whose vehicles: 1) are not equipped with a muffler; 2) clearly emit an offensive, harsh, excessive noise, or, 3) have a clearly defective exhaust system (holes, leaks, etc.). Clearing Citations When clearing excessive noise citations issued by the CHP or allied agencies, personnel are to consider exhaust systems in compliance if they incorporate a reasonably effective muffler, do not emit an offensive, harsh, excessive noise, and appear to be in good repair.