Muffler or Exhaust?
Originally mufflers comprised a long pipe that channelled exhaust fumes to the back of the vehicle and a resonator that cancelled out the sound from a device fittingly named the combustion engine! Made of soft metal, mufflers rusted easily and had to be replaced often.
These days mufflers are usually made of stainless steel and have to be replaced much less frequently. Nonetheless, they still require maintenance, as they’ve evolved into complex devices that do much more than simply reduce noise.
Modern exhaust systems now include many components to process the engine exhaust. In most vehicles, the front part of the system is made of a flexible tube that absorbs the vibrations of a transverse engine. Like the rest of the system, this part is exposed to inclement weather, heat, and cold, as well as impacts from potholes and bumps. That’s why it’s important to get the exhaust system inspected whenever you get your oil changed or if it starts making unusual noises.
The catalytic converter is the main component of this system. To comply with government regulations and protect the environment, it converts toxic gases (carbon monoxide, unburned hydrocarbons, nitrogen oxide, etc.) into less harmful gases which are then expelled into the atmosphere. Made of precious metals and equipped with a sensor, it’s the most expensive part of the exhaust system. A catalytic converter is usually guaranteed for up to 160,000 km but, if the engine is poorly maintained, it may become ineffective, the Check Engine light on the dashboard will come on, and the converter will have to be replaced.
The rest of the system should be inspected visually on a regular basis, including the rear exhaust pipe, which may produce a low rumbling noise in the case of sports cars, and especially the clamps, hangers, and heat protection elements that hold it onto the vehicle. With proper preventative maintenance, few repairs will be required.