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What is a Catalytic Converter? What Does it Do?

Catalytic Converter

Emissions standards are getting more and more strict all the time. One significant way your vehicle controls emissions is through the catalytic converter. All the exhaust from your engine passes through it before exiting the tailpipe.

The catalytic converter is a honeycomb chamber of palladium, rhodium, and platinum. As the exhaust passes through this chamber, a chemical reaction occurs between the precious metals and the exhaust. This reaction reduces the amount of nitrogen dioxide and nitrogen oxide in the exhaust. The final stage in the catalytic converter’s job is an O2 sensor that relays how much oxygen the fuel has to your car’s ECU. This allows the engine to adjust the air-to-fuel ratio, thus improving the emissions quality.

Your car would function without the catalytic converter. However, it is a crucial part of the emissions system. Without it, your vehicle will be doing serious damage to the environment—especially an older vehicle. Not only that, but because of where the catalytic converter is located, the risk of other parts of your exhaust system falling off is high if you drive without it.

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Where is the Catalytic Converter Located?

The catalytic converter is located in different places depending on the vehicle, but it is always between the engine and the muffler. As a general rule, it is located approximately one-third of the way between the two—usually closer to the engine side.

If you look under your car, you will notice something that looks almost like a second muffler; this is the catalytic converter. On most vehicles, it’s relatively easy to access. This ease of access leads to a high rate of theft.

Between the change of sound and a check engine light, the chances are pretty high that you will know as soon as you fire up your vehicle if it goes missing. However, knowing where the catalytic converter is located will enable you to rule that out quickly if you are unsure.

Catalytic Converter Close up
Image By: Ulianenko Dmitrii, Pixabay

Why is Catalytic Converter Theft a Thing?

Chances are pretty high that the catalytic converter probably won’t wear out even if you own your vehicle for more than 10 years. And lots of times it gets too dirty, you can actually buy kits that help clean it out to give it more life. Theft, on the other hand, is a different story.

Catalytic converter theft is prevalent for two main reasons. These components are pretty costly to replace, so thieves will steal them from vehicles and then sell them to illegally operated automotive shops. These shops will then sell them at a lower cost to people who don’t care where the parts come from.

The other reason they are attractive to thieves is the extreme value of the precious metals they contain. These metals can fetch thousands of dollars on the market for only ounces of the metal. Before you start thinking that catalytic converter theft is a good side hustle, you have to realize the amounts of these metals in the catalytic converters are very small. You would also need a way to extract the metals. It takes a dedicated criminal to make that happen.


Now, you know where the catalytic converter is located and what it does. It’s honestly pretty incredible that such a seemingly simple system can make such a massive difference. Simply by harnessing a natural reaction between exhaust chemicals and precious metals, scientists have figured out a way to make the air cleaner. And now, with the push into battery-powered automobiles, they are taking this even further!

Featured Image Credit: Ulianenko Dmitrii, Shutterstock

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