The purpose of an exhaust system is to control & expel engine exhaust from the engine, to the back of the vehicle. It has to be a solid, closed system, because there are sensors in the exhaust that help control engine operation.

It also helps to reduce the noise that an engine generates from running.

What’s In An Exhaust System

An exhaust system is made up of:

  • an exhaust manifold
  • a muffler
  • a catalytic converter
  • oxygen sensors (unless your car is pre-1986)
  • and pipe to join it all together

These are the basic parts of an exhaust system.

Recognizing Exhaust Leaks

If your car has a leak, you will usually notice one of a few things:

  • the engine will seem louder than normal
  • there will be funny smells that you never noticed before
  • your check engine light may turn on.

It may be tempting to just leave an exhaust leak without fixing it. After all, a leaky exhaust won’t leave you stranded. I would be concerned about safety in the case of an exhaust leak, and here’s why.

Why Fix An Exhaust Leak?

Carbon monoxide is an odourless, tasteless gas that can kill you if you inhale too much. If you have an exhaust leak, it’s possible for carbon monoxide to leak into your car (where you’re breathing!).

You’ve probably seen on movies where someone attempts to kill themselves by locking themselves in a garage with the car running, right? I can faithfully say that you wouldn’t want to do that accidentally. You can’t just “ignore” an exhaust leak.

It’s not about the health of the car, it’s about your health (or your children’s if they ride with you).

Beyond safety concerns, exhaust leaks can cause:

  • poor gas mileage
  • annoying noises, vibrations, rattles, and a loud droning sound
  • potential fire hazards
  • if your car is turbo-charged, your car may lose power

In one situation I had with a customer, the exhaust leak was under the floorboards of the car. The heat from the leak was so tremendous that the carpet of the vehicle actually started smoking as it was being ignited.

Fire is bad!

The Cost Of Exhaust Parts

Most exhaust system repairs do not outright replacing of the entire system. Exhaust systems are like lego – they come apart! If one part is bad, you can just replace that part and the problem will disappear.

Newer exhaust systems have alloys in the metal so they don’t rust easily. This makes exhaust parts more expensive, but it also makes them last longer.

The piping in between parts is the cheapest part of the system, while components like a catalytic converter are expensive.

Because exhaust systems are so varied, I can’t determine an average cost of repairs. It depends entirely on how much of the original exhaust system can be saved, and what type of vehicle you have; large trucks are often more expensive than small cars.

Optional Exhaust Parts

Some cars have optional add-ons to their exhaust system for extra performance. Parts such as:

  • dual tailpipes
  • dual exhaust
  • resonators (to further reduce the noise of an engine)
  • larger-diameter pipes (to increase power)
  • free-flowing exhaust manifolds (aka “headers”)
  • free-flowing mufflers
  • heat risers (for older v8 engines)

Most of these optional parts aren’t relevant to the average driver, and they’re only emissions related anyways. They’re more useful to guys who want to do high-performance upgrades on their car.