Q: How to tell if I need a new catalytic converter

asked by on December 16, 2015

I think I need a new catalytic converter, but I am not sure. How do I have this diagnosed?

Hey thanks for the question, and thats a really good one by the way. As technology has grown so has the demand for more fuel efficient cars that are more friendly on the environment. One way this is achieved is by the use of a "catalyst converter" in your exhaust system. To help you understand how it is diagnosed lets look at what it is and what its job is. Your engine burns gasoline for combustion which is basically a controlled explosion, and the by product of combustion is gases that destroy our ozone and are harmful to the environment. These gases are the blame for "smog" in larger cities and many other environmental hazards. And no matter how efficient we make engines, in the end these gases are still present just in smaller amounts. That is where the catalyst converter comes in. It is installed in your exhaust pipe like a filter before your exhaust is released to air. The catalyst is made up of several layers of precious metals, like titanium, platinum, and rhodium, and these layers of metal form like a honeycomb that your exhaust passes through.

Once the catalyst is heated up, it goes to work as your exhaust passes through the reaction of the carbon dioxide, carbon monoxide, and hydrocarbons. As it meets those metals those gases are transformed into clean air and water. Yes, water. A little known fact! Haven’t you been behind a car at a red light and seen water dripping out the tail pipe? That is just its converter hard at work.

Now this converter could cause you problems in a couple of different ways, it could fail, causing your check engine light to come on and your car to fail an emission test. Or the plates could melt together causing a major restriction in your exhaust. So you would need the expertise of a certified technician who understands the emission system on your car as well as the exhaust system to fully diagnose your issue, and determine if your catalytic converter needs to be replaced

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