Diagnose and Repair Your Leaky Exhaust
If the exhaust is loud on your vehicle, it’s time to check for an exhaust leak. Exhaust can leak from holes in the exhaust manifold, flex pipe, catalytic converter, mid-pipe, or muffler, or from worn gaskets in these areas. Exhaust leaks can also manifest as black soot from carbon dioxide and contaminants. Leaks near the front or middle of the vehicle could find ways into the cabin via open windows or holes in the floorboards or firewall.
Watch this video or read on to learn why it’s important to inspect it and fix it as soon as possible.
Checking for An Exhaust Leak
Steps to check for an exhaust leak
- If Working in an Enclosed Area, Confirm It’s Ventilated
If you’re inspecting the vehicle’s exhaust in an enclosed area like a garage, make sure it’s well ventilated. Since the exhaust system expels carbon dioxide, it’s very important these fumes can exit your workspace.
- Visually Inspect for Holes, Worn Gaskets, and Black Soot
Starting with the exhaust manifold, visually inspect the exhaust parts down to the muffler for leaking areas on these parts or their gaskets. Also inspect the exhaust parts for black soot, which is a remnant of carbon dioxide and other contaminants.
- Listen for Loud Sounds Caused By an Exhaust Leak
Start the vehicle and listen to the exhaust to find a good starting point. Since exhaust pipes can run hot, do not touch the exhaust but place gloved hands near suspected leaking points and feel for any air. Go along the exhaust, inspecting each part. If you feel air coming from an area, it’s probably leaking.
With your hand in a glove, place your hand on the end of the exhaust and feel for pressure. A well-working exhaust will have enough force to push your hand back. A leaking exhaust will have little to no pressure, meaning there is an exhaust leak. If this happens, have an assistant place their hand over the end of the tailpipe and inspect the exhaust system with your hands for escaping air without touching the parts. - Inspect an Exhaust Leak with a Mirror
If you can still hear a leak but none of the above methods worked, try inspecting the leaking parts with a mirror. Bring the mirror near the suspected leaking part, and if the mirror glass fogs up, there’s a leak.
- Inspect the Condition of the Remaining Exhaust Parts
Depending on where the leak is in the exhaust system, consider replacing other parts that may be deteriorating or worsening in condition.
If parts of the exhaust are leaking, it’s important to replace them asap as leaks could find ways into the cabin, putting passengers’ safety at risk.
Shop Quality Auto Parts
How to Replace a Flex Pipe Yourself
Check out this video below and learn how to replace a flex pipe yourself. For videos on other exhaust parts, check out the 1A Auto how-to video library.
Shop Parts Needed to Repair an Exhaust Leak
Content Related to Exhaust Leaks
- What Is an O2 Sensor?
- Can a Bad O2 Sensor Cause a Misfire?
- Exhaust Manifolds Vs. Headers
- Exhaust Manifolds 101
- P0171 code – What it means, symptoms, causes, and how to fix it