Oakley, CA Noise Ordinances: Vehicle Noise (2026)
Key Facts
- Muffler requirement
- CVC 27150 – adequate muffler
- Max dBA
- 95 dBA (CVC 27151)
- Stereo limit
- Audible <50 ft (CVC 27007)
- First fine
- $100–$200 + fix-it
- Sideshow
- Impoundment possible
Summary
Oakley enforces California Vehicle Code Section 27150 requiring adequate, unmodified mufflers on all vehicles, along with OMC Chapter 8.20 prohibitions on excessive vehicle noise. Modified exhausts, engine revving, and audio systems audible 50+ feet away from the vehicle are all subject to citation.
27150.
(a) Every motor vehicle equipped with an internal combustion engine and subject to registration shall at all times be equipped with an adequate muffler in constant operation and properly maintained to prevent any excessive or unusual noise, and no muffler or exhaust system shall be equipped with a cutout, bypass, or similar device.
(b) Except as provided in Division 16.5 (commencing with Section 38000) with respect to off-highway motor vehicles subject to identification, every passenger vehicle operated off the highways shall at all times be equipped with an adequate muffler in constant operation and properly maintained so as to meet the requirements of Article 2.5 (commencing with Section 27200), and no muffler or exhaust system shall be equipped with a cutout, bypass, or similar device.
(c) The provisions of subdivision (b) shall not be applicable to passenger vehicles being operated off the highways in an organized racing or competitive event conducted under the auspices of a recognized sanctioning body or by permit issued by the local governmental authority having jurisdiction, or to vehicles not equipped with an internal combustion engine. (Amended by Stats. 2021, Ch. 428, Sec. 9. (SB 570) Effective January 1, 2022.)
Official source re-checked September 8, 2026: the cited page had not changed since it was quoted.
Full Breakdown
20. CVC Section 27150 requires every motor vehicle to be equipped with an adequate muffler in constant operation and prohibits modifications that amplify or increase exhaust noise. CVC Section 27151 bars any alterations that cause the vehicle to exceed 95 dBA under a SAE J1169 measurement. Oakley police enforce these against modified exhaust systems, straight pipes, and deleted catalytic converters: increasingly common issues on modified trucks along Main Street and Highway 4 corridor. Vehicle audio systems (car stereos) that can be heard 50 feet or more from the vehicle violate CVC 27007 and are commonly cited along Oakley's Delta waterfront cruise routes.
Engine revving, prolonged idling, and "burnouts" or "sideshows" are separately prohibited under both state and local law and may result in vehicle impoundment under recent California sideshow enforcement statutes. Fines for a first muffler violation typically run $100–$200 plus a required "fix-it" correction showing compliance before the citation is signed off. Motorcycle noise complaints are frequent given Oakley's popularity with Delta-area riders.
Frequently Asked Questions
Are aftermarket exhausts ever legal in California?
Can I be cited for revving my engine in my own driveway?
What about diesel trucks with loud engines?
Sources & Official References
Other rules in Oakley
California rules heatmap·Compare Oakley to another location·View the California noise ordinances overview
See something wrong?
Help us keep this page accurate. If you notice an error or outdated information, let us know.
Vehicle Noise in Nearby Cities
How other cities in Contra Costa County handle vehicle noise.