Code of Maryland Regulations › Title 11 - DEPARTMENT OF TRANSPORTATION › Subtitle 14 - MOTOR VEHICLE ADMINISTRATION-VEHICLE INSPECTIONS › Chapter 11.14.02 - Safety Standards for Passenger Cars, Taxicabs, Light Trucks, Vans, Multipurpose Passenger Vehicles, and Type II School Vehicles › Section 11.14.02.06 - Exhaust System

Current through Register Vol. 51, No. 14, July 12, 2024
A. The exhaust
				system includes the exhaust manifold and all piping leading from the flange of
				the exhaust manifold, to and including the muffler, resonator, and the tail
				piping.
Procedures:
Reject Vehicle If:
(1) With engine running and the vehicle on a hoist or
						  lift, visually inspect the exhaust pipes, mufflers, resonators and tail pipes
						  for leaks, deterioration, proper mounting, damage, and general condition.
						  Rusted or corroded areas shall be given particular attention. Holes in the
						  system made by the manufacturer for drainage are not cause for rejection.
(1) Vehicle has no muffler.
(2) Light trucks equipped with a cap or slide-in camper
						  shall have a full length tail pipe extending beyond the rear wheels and exiting
						  beyond the side or rear of the body.
(2) There are loose or leaking seams or joints.
(3) On all other vehicles the tail pipe shall be located
						  as originally designed by the vehicle manufacturer, or if not as originally
						  designed shall extend beyond the passenger or occupant compartment and enclosed
						  cargo area if it is open to the driver or passenger area. The tail pipe shall
						  extend at least to the front of the rear wheels, beyond the rearmost door
						  opening, and exit beyond the side or rear of the body.
(3) There are holes caused by damage, corrosion, or
						  temporary repairs made to the exhaust pipe, muffler, resonator, or tail pipe.
						  Welding or brazing is considered a permanent repair if it does not
						  leak.Elimination of a resonator alone is not cause for rejection as long as the
						  vehicle has an effective muffler.
(4) Type II school buses shall have a full length tail
						  pipe extending beyond the rear wheels and exiting beyond the side or rear of
						  the body unless the vehicle is equipped with a left side exhaust system which
						  meets the following criteria:
(4) Tail pipe end is pinched or obstructed.
(a) The exhaust pipe may not passwithin 12 inches of the
						  fuel tank or its connections unless a suitable baffle is installed between the
						  exhaust system and these components.On vehicles with left side mounted fuel
						  tanks, compliance with this requirement may be more difficult; however, this
						  requirement shall still be met.
(5) The system is not properly mounted, securely
						  fastened, or if the seam of a muffler or resonator on a type II school vehicle
						  faces the fuel tank, fuel lines, or floor of the vehicle.
(b) No part of the exhaust system may pass within 12
						  inches of any flexible brake hose, solid brake line, or flexible fuel line
						  unless a suitable baffle is installed between the exhaust system and these
						  components.
(6) There are loose muffler baffles; the vehicle is
						  equipped with cutout or similar device; or the system is not original or
						  equivalent.
(c) The exhaust pipe should be approximately a 45-degree
						  angle as it approaches the left body line to prevent back pressure and heat
						  buildup (see diagram).
(7) Any part of the system passes through the occupant
						  compartment, or there are any leaks in the heat exchange boxes or ducts of
						  vehicle using engine exhaust heat to warm the interior of the vehicle.
(d) The exhaust pipe shall be deflected downward as it
						  approaches the left side of the body.
(8) The tail pipe on light trucks equipped with a cap or
						  slide-in camper or a type II school vehicle is not full length, or does not
						  extend beyond the rear wheels and exit beyond the side or rear of the
						  body.
(e) The exhaust pipe shall exit behind the driver's
						  compartment.
(9) The tail pipe on all other vehicles, if not as
						  originally designed by the vehicle manufacturer, does not extend beyond the
						  occupant compartment and the enclosed cargo area if it is open to the occupant
						  compartment, to at least the front of the rear wheels and beyond the rear of
						  the rearmost door opening, or does not exit beyond the side or rear of the
						  body.
(10) Exhaust pipe, muffler, or tail pipe is not of a leak
						  proof construction. Flexible pipe that does not leak is acceptable, except on
						  type II school vehicles.
(11) It emits continuous exhaust fumes or smoke which
						  obscures persons or objects from a clear rear view.
(12) On the type II school vehicle, the system passes
						  directly under the emergency door, or there is any reduction in the size of the
						  tail pipe after it leaves the muffler.
(13) A type II school vehicle with left side exhaust does
						  not meet the requirements established.