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Four Exhaust Leak Warning Signs

The exhaust system is made of piping that guides harmful exhaust gases away from the engine and into the atmosphere. Exhaust gas typically flows through the exhaust manifold, catalytic converter, resonator and finally the muffler, which connects to the tail pipe. Each of these parts needs to function properly for the system to work.

When there's a problem, poisonous gases that are colorless and odorless can travel into the passenger cabin, putting you and your passengers at serious, potentially fatal risk. If you notice any of the symptoms below, make an appointment at your local service center as soon as possible.

1. Hissing or Popping Noises

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The biggest clue to look for is an intermittent hiss or popping noise while the engine is running. This may be accompanied by discolored or burned paint next to the exhaust ports on the cylinder head or burned spark plug wires or boots.Also pay close attention to the quality of the sound coming from the tailpipe. A high-pitched hiss or whistle at the tailpipe may be the result of a restriction in the exhaust system and unusually high backpressure.

2. Small Leaks

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The thermal expansion and contraction that occurs every time an engine is started creates stress on the exhaust manifold gasket. Over time, small leaks can develop, and eventually they get bigger. To inspect for small leaks, start at the engine and go all the way back to the tailpipe. A good place to check is where the exhaust manifold mates to the cylinder head.

3. Vibration

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You might notice a new vibration when you touch the steering wheel, foot pedals or car seat. It could be due to a rusty exhaust. Particularly on vehicles that take a lot of short trips, the muffler and pipes don't get hot enough to evaporate collected water, condensation just sits there, and sooner or later the system rusts. If you notice a new vibration or loss of power when operating your car, have the exhaust system checked by a professional.

4. Reduced Gas Mileage

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If the engine lacks high-speed power and is getting poor fuel mileage, there is a good chance the engine is having trouble exhaling. Similar to vibrations, increased fuel use is a sign that something may be wrong with your car. When there is an exhaust leak, your engine has to work harder. And when your engine works harder, it requires more fuel. If you notice that you have to fill up your gas tank more often than normal, have your exhaust system checked out by your local Pep Boys.


Exhaust noise always means trouble. But even if you can't hear anything, it may be leaking. Always check the exhaust system while your engine is running. A live test is better because the exhaust leaks are usually obvious when your car is on. A visual inspection of the rest of the exhaust system will usually reveal any obvious problems such as holes in the muffler and cracked or damaged pipes.

On vehicles that are more than 5 years old, it is a good idea to have a thorough inspection of the exhaust system once a year to check for leaks and other damage. Even if no leaks are immediately visible, the inspection may uncover loose parts or minor damage that can be repaired before it becomes major damage. Depending on your car and its exhaust system, the cost to make repairs to a damaged or broken exhaust component can vary widely. But putting off an exhaust repair almost always costs more than addressing them promptly.

If you are worried something may be wrong with your exhaust system,
schedule an appointment today with your local Pep Boys service center.

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