67 Pa. Code § 175.181
(b) Exhaust system requirements. A vehicle specified under this subchapter shall be equipped with a muffler or other effective noise-suppressing system in good working order and in constant operation. A muffler or exhaust system may not be equipped with a cutout, bypass or similar device and a muffler may not show evidence of external repair.
The provisions of this § 175.181 amended under the Vehicle Code, 75 Pa.C.S. § § 4103, 4301, 4501, 4521 and 6103.
The provisions of this § 175.181 adopted October 29, 1982, effective February 1, 1983, 12 Pa.B. 3862; corrected November 12, 1982, effective February 1, 1983, 12 Pa.B. 3947; readopted December 2, 1988, effective December 3, 1988, 18 Pa.B. 5362; amended November 13, 1998, effective May 13, 1999, 28 Pa.B. 5670. Immediately preceding text appears at serial pages (221311) to (221312).