An exhaust manifold leak can allow toxic engine exhaust into the cabin of your vehicle and also reduce your vehicle’s efficiency. The exhaust is carbon monoxide gas and is odorless and colorless, and extremely dangerous to you and your passengers. A leaking manifold is also dangerous for your engine, it can cause a burned exhaust valve, which will lead to other problems. You can hear a leaking exhaust manifold really well. The sound will come from the engine area and not from under the car. Do not mistake a leaking exhaust manifold from a leaking exhaust muffler. Make these checks to ensure your exhaust is being properly delivered out the exhaust pipe at the rear of your vehicle.

Things to Look Out For



The carbon monoxide doesn't have any color or odor, but other fumes are noticeable. If you're noticing a strong smell, particularly an exhaust or a burning smell, in your cabin while the car is running, you may have a leak.


Poor Power and Acceleration

If your engine is under-performing, an exhaust leak may be to culprit. An under-performing engine will usually get worse over time, so run most checks or take the car in to a mechanic to determine the exact problem.



Engines are pretty good about making odd sounds when something is wrong. If your engine is especially loud, a burned gasket or cracked manifold pipe may be the allowing exhaust to leak where it isn't supposed to.


Cracked Pipe

The most visibly obvious sign of a leak is a cracked pipe in the exhaust manifold rigging. Because this is under the car, it needs to be checked at a specialty shop or on a lift.

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