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How to Fix an Exhaust Leak (Step-by-Step)

Updated: Jan 8

An exhaust leak can be a frustrating problem for any vehicle owner. Not only can it lead to decreased performance and fuel efficiency, but it can also be dangerous as it can allow carbon monoxide to leak into the cabin of the vehicle.


In this article, we will outline the symptoms of an exhaust leak, whether it is possible to repair an exhaust leak yourself, the potential dangers of driving with a leaking exhaust, and the various methods on how to fix an exhaust leak.

 

Table of Contents:


mechanic working on a car exhaust

Exhaust Leak Symptoms

There are several symptoms of an exhaust leak you should look out for if you suspect your vehicle may have one.


  • Unusual sounds: A leaking exhaust can produce a range of unusual noises such as hissing, whistling, or tapping.

  • Smell of fuel: If you smell fuel of exhaust fumes inside your vehicle, it could be a sign of an exhaust leak.

  • Reduced engine performance: An exhaust leak can reduce the overall performance of your engine, leading to a decrease in power and acceleration.

  • Check engine light: In some cases, an exhaust leak can trigger the check engine light to come on.


an exhaust leak on a rusy exhaust pipe

Can You Repair an Exhaust Leak Yourself?

Whether you can repair an exhaust leak yourself will depend on your level of mechanical expertise and the tools you have available. Some smaller exhaust leaks may be fixable with an exhaust repair kit, which can be purchased from an auto parts store or online (such as here).


However, more significant leaks may require welding or other more advanced repairs that are best left to a professional mechanic.


Can You Drive With a Leaking Exhaust?

It is generally not recommended to drive with a leaking exhaust. Here are some reasons why.


  • Fails emissions testing: A leaking exhaust can lead to your vehicle failing an emissions test, which may be required in some areas.

  • May be illegal: In some areas and countries, it is illegal to drive a vehicle with a leaking exhaust as it can be considered a safety hazard and fails emissions testing.

  • Can cause issues with the vehicle: An exhaust leak can lead to decreased performance and fuel efficiency, as well as potentially damaging other components of the vehicle.

  • Can be dangerous (carbon monoxide): Perhaps most importantly, a leaking exhaust can allow carbon monoxide to enter the cabin of the vehicle, which can be deadly.


How Much Does It Cost to Fix an Exhaust Leak?

The cost to fix an exhaust leak will depend on the location and severity of the leak, as well as the type of repair needed.


Some minor repairs, such as sealing a small hole with an exhaust repair kit, may cost as little as $10-20 (£8-15 / €9-18).


However, more significant repairs, such as welding a new section of exhaust pipe or replacing the section, can cost upwards of $100 or more (£80 / €90).


How to Find an Exhaust Leak (Soapy Water Method)

One simple way to locate an exhaust leak is to use the soapy water method. Here's how it works.


  1. Mix up a solution of water and dish soap in a spray bottle.

  2. Start the engine and let it idle.

  3. Spray the solution onto various parts of the exhaust system, paying particular attention to any joints or seams.

  4. If you see any bubbles forming, it indicates a leak in that area.


Can You Fix an Exhaust Leak Temporarily?

If you are unable to get your exhaust leak repaired immediately, there are a few temporary fix options you can try.


  • Use an exhaust leak repair kit: These exhaust repair kits contain a sealant that can be applied to small holes in the exhaust system to temporarily seal the leak.

  • Use exhaust putty/cement: Exhaust putty or cement can be used to temporarily seal small holes or cracks in the exhaust system.

  • Use exhaust tape: Exhaust tape is a strong, heat-resistant tape that can be used to seal small holes or cracks in the exhaust system.


However, it is important to note that these temporary fixes are only meant as a stopgap measure and should not be relied on long-term.


How to Fix an Exhaust Leak

If you have determined that your exhaust leak requires a more permanent repair, there are a few options you can try.


  • Use an exhaust clamp: If the leak is located at straight section or a joint in the exhaust system, an exhaust clamp can be used to clamp the joint together and seal the leak. An exhaust clamp can be used in combination with exhaust putty or tape to be more affective

  • Weld a new section of exhaust in: If the leak is located in a section of the exhaust pipe, it may be necessary to remove the damaged section and weld in a new one.


How to Fix an Exhaust Leak Without Welding

If you do not have access to welding equipment or do not feel comfortable attempting a welding repair, there are a few non-welding options you can try.