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Auto | Under the Hood | Exhaust & Emissions

This section can help you keep your exhaust system working properly. Learn how mufflers, catalytic converters and oxygen sensors work.

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How does the oxygen sensor in a car work?

An oxygen sensor in a car is a very important part of making your engine run smoothly. Learn what it does and what can happen if your oxygen sensor fails.


 What is a catalytic converter and how does it work?

What is a catalytic converter and how does it work? See more »