Section 51. Mufflers and Smoke. —

Every motor vehicle propelled by an internal combustion engine shall be equipped with a muffler, and whenever said motor vehicle passes through the street of any city, municipality, or thickly populated district or barrio, the muffler shall not be cut out or disconnected. No unnecessary or disagreeable odor, smoke or noises of any kind shall be given off, emitted, caused or made by any motor vehicle in the places mentioned in this section.