A broken or leaky exhaust system can make your car loud and annoying. However, the obnoxious noise may be the least of your worries.
Exhaust systems are carefully tuned so that combusted air and fuel are transported from your engine to the rear of your car as efficiently as possible. Leaks in your exhaust system will cause turbulence within the piping that can hinder your engine's horsepower output and fuel efficiency.
Furthermore, exhaust leaks can be potentially lethal. If your exhaust system is leaking, carbon monoxide and other dangerous gases can seep into your car's interior, potentially poisoning you and your passengers. That's why it's imperative that you troubleshoot and repair issues with your car's exhaust system as soon as they arise.
Use Your Car's Diagnostic System
Most car exhaust systems have integrated oxygen sensors and other electronic diagnostic tools. Sometimes these sensors will pick up an exhaust leak and trigger your car's check-engine light. In that case, all you have to do is take your car to a reputable auto repair center and have the mechanics connect a diagnostic computer to your car. That will allow them to determine roughly where the leak is coming from so they can perform the necessary repairs.
Get Under Your Car
To fully inspect the exhaust system, you have to get underneath your car. Park it on a flat surface and engage the emergency brake. Then, use a floor jack to raise your car and slide jack stands under the chassis. You can find the proper locations to place jack stands by consulting your vehicle owner's manual.
Check for Rust and Holes
The exhaust piping hangs underneath your car, making it subject to water, road salt, and other road debris. That means it is prone to becoming rusted or otherwise damaged over time.
Use a flashlight to visually inspect the entire length of the exhaust piping. Pay especially close attention to the welds along exhaust flanges, as those are the mostly areas to crack due to engine vibrations. If any sections of the piping have extensive rust or holes, those sections need to be repaired. Depending on the extent of the damage, an automotive repair shop may be able to cut out the affected area and weld in a patch. Otherwise, the entire section of piping needs to be replaced.
Check the Exhaust Gaskets for Soot
Most exhaust systems consist of multiple sections to allow the piping to wind along the underside of your vehicle. Each section is connected to the next with a flange, and the flanges are sealed with rubber gaskets. Your exhaust system gets extremely hot every time you drive your car, which can cause the gaskets to melt and leak over time.
Generally, a leaky exhaust gasket expels soot that will coat the metal area around the seal. If any of the exhaust flanges are covered in soot, the cause of your exhaust leak is likely a worn-out gasket. Luckily, replacement gaskets are relatively cheap compared to repairing or replacing the exhaust piping.
Your car's exhaust system may seem like a relatively simple component compared to the complex components of your engine. Nevertheless, exhaust leaks can affect your car's performance in significant ways and subject you to dangerous fumes. Always repair exhaust leaks as soon as they arise, regardless of how minor they may seem.