The purpose of the Muffler is to reduce the noise emitted by the exhaust of an internal combustion engine. Mufflers often wear over time from rust due to condensation build up. As the engine cools down after use, the change in temperature creates a build up of condensation. Excessive noise, exhaust, or change in your engine's exhaust tone are signs that a muffler is damaged. A damaged muffler can allow for excessive noise, reduce fuel economy, and impact the performance of your machine.