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Signs Of An Exhaust Leak


In terms of automotive repairs, exhaust leaks can be easy or difficult to identify. Due to the complexity, length, and exposure to outside elements of each exhaust system, the symptoms and side effects of an exhaust leak vary. 


Connected to your engine and running the length of your vehicle, the exhaust system is a workhorse! It transports heat and noxious gases from fuel combustion out and away from your vehicle, while also muffling the sound of your motor as it burns fuel to power you down the road. The exhaust plays a critical role in keeping you and your passengers safe from carbon monoxide while also ensuring your vehicle burns fuel as efficiently as possible without overheating. 


When your exhaust develops holes or leaks, your vehicle will still run, but you’ll likely notice signs that things aren't right. Exhaust leaks vary in severity, so while you could ignore one and suffer only sluggish performance, over time they may develop into more significant issues that require a more expensive repair. If you suspect you have an exhaust leak, you should have it addressed as soon as possible.

Check under the hood


If you're experiencing any of the following symptoms while your vehicle is idling or driving, you may have an exhaust leak.


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Reduced Fuel Economy - Does it seem like you fill up more often or that your average gas mileage is reduced? If so, this may be a sign of an exhaust leak. Holes in your exhaust can also draw in outside air and, in some cases, this leads the O2 (oxygen) sensor to think the engine is running lean (too much air and not enough fuel in the combustion process). To compensate, the O2 sensor will tell your vehicle to inject extra fuel, leading to unburnt gas in the exhaust and other components. Over time, this poor fuel mixture can collect and cause other problems. 


Engine Noise - Does your vehicle sound different recently? Has it grown louder? If yes, this can be a telltale sign of an exhaust leak. A main functions of your vehicle's exhaust is to dampen the noise of the engine as it burns fuel. If your vehicle seems louder than usual, have it checked by a professional. 


Gas Smells - Have you started smelling gas or fumes inside your vehicle? Your vehicle cabin draws air in from around your vehicle, so if you smell fuel or exhaust gas inside the cabin, you may have an exhaust leak. This symptom is particularly dangerous as carbon monoxide poisoning is a threat to both you and your passengers. 


If you’re wondering how to fix an exhaust leak, you shouldn't wait to get it looked at. Although your vehicle may run just fine or with slightly reduced performance, over time the expense of a simple repair will seem small when compared with the extra fuel you’ll need to burn to compensate. Exhaust leaks also cause a great deal of pollution and can be dangerous if they’re venting noxious fumes into the vehicle cabin, so if you’re experiencing an exhaust leak, don’t delay.