CVC 27151(a)Eligible for written declarationCorrectable

Modified Exhaust That Increases Noise

Modifying a vehicle's exhaust system so it amplifies or increases engine noise beyond what Vehicle Code 27150 or the noise limits for that type of vehicle allow, or driving a vehicle with an exhaust modified that way.

Reviewed by the TicketClear teamLast reviewed October 10, 2026

Fine: check your notice or your court's bail scheduleDMV Points: None✓ Correctable

This guide is for general educational purposes only and does not constitute legal advice. TicketClear is a self-help document preparation service — we are not attorneys and do not represent clients. Review all prepared documents carefully before submitting. Fine amounts are estimates and vary by county and surcharge schedule.

What is a Modified Exhaust That Increases Noise ticket?

CVC 27151(a) says a person shall not modify the exhaust system of a motor vehicle in a manner which will amplify or increase the noise emitted by the motor so that the vehicle is not in compliance with Section 27150 or exceeds the noise limits established for the type of vehicle in Article 2.5 (commencing with Section 27200). A person shall not operate a motor vehicle with an exhaust system so modified.

Ask your insurer how a conviction affects your policy.

What the Law Says

(a) A person shall not modify the exhaust system of a motor vehicle in a manner which will amplify or increase the noise emitted by the motor of the vehicle so that the vehicle is not in compliance with the provisions of Section 27150 or exceeds the noise limits established for the type of vehicle in Article 2.5 (commencing with Section 27200). A person shall not operate a motor vehicle with an exhaust system so modified.

What the Officer Must Prove

1The exhaust system of the motor vehicle was modified
2The modification amplified or increased the noise emitted by the motor so that the vehicle did not comply with Section 27150 or exceeded the noise limits for its type in Article 2.5
3You made the modification, or operated the vehicle with it

Arguments Commonly Raised for Modified Exhaust That Increases Noise

General information: arguments drivers commonly raise for this code section. Whether any applies depends on your own facts.

No modification

CVC 27151(a) applies to a modified exhaust system. If the system was the original equipment, describe it and keep any records.

Noise not increased beyond the limits

The section applies when the modification amplifies or increases the noise so that the vehicle does not comply with Section 27150 or exceeds the noise limits for its type. Describe any test or inspection you have.

Correction

If your notice is marked correctable, keep proof of the correction.

⚠️ Common Mistakes

✗Not keeping records of the exhaust parts installed
✗Not keeping proof of correction

What this code section covers (general information)

CVC 27151(a) — Modified Exhaust That Increases Noise. Modifying a vehicle's exhaust system so it amplifies or increases engine noise beyond what Vehicle Code 27150 or the noise limits for that type of vehicle allow, or driving a vehicle with an exhaust modified that way.

Eligible for Trial by Written Declaration: generally yes.

This is general information about CVC 27151(a). It is not advice about your citation, and TicketClear does not evaluate anyone's facts. Whether any of it applies depends on your own facts. For advice about your situation, consult a licensed California attorney.

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Related Violations

CVC 27150(a)CVC 24002(a)