This bill amends existing New Jersey law to prohibit the installation or modification of a motor vehicle's muffler or exhaust system in a way that amplifies or increases the noise emitted beyond what was originally installed. The penalties for violating this provision include a fine of up to $500, imprisonment for up to 30 days, or both. Additionally, the bill mandates that motor vehicle inspections must now include checks for excessive or unusual noise from mufflers and exhaust systems, expanding the scope of inspections beyond just emissions and emission-related items.

The bill also introduces new legal language regarding the requirements for vehicle horns and the use of audible warning devices. It specifies that every motor vehicle must be equipped with a functioning horn that does not emit an unreasonably loud sound, and it restricts the use of sirens, whistles, or bells on vehicles, with exceptions for emergency vehicles. Furthermore, the bill empowers the commission to establish standards for the audibility of warning devices and outlines the penalties for violations related to these provisions, aligning them with existing penalties for similar infractions.