Tips For Troubleshooting The Most Common Vehicle Error Code

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When the service engine light comes on in your vehicle, you'll need to take it to an auto shop or local auto parts store to have someone read the code for you. This is done by plugging in a computer that identifies the code, which can then be used to look up the specific problem. The most common error code that comes up is P0420, which identifies a problem with the catalyst system's low efficiency. This can make you wonder what that even means, which is why it helps to know some of the common problems that can cause this code to show up. 

Know Why The Error Code Appears

Error code P0420 will show up when the oxygen sensors in your vehicle have identified a problem with the catalytic converter not working properly. There is a sensor located before and after emissions flow through the catalytic converter, which helps monitor how the catalytic converter is handling those emissions. For example, if the sensors read the same data from the exhaust before and after it enters the catalytic converter, it means that the catalytic converter isn't doing anything to limit the exhaust. 

Know The Parts That Can Be Damaged

There are two potential parts that have a high chance of being damaged with this common error code. You either have a problem with the catalytic converter itself, or the sensors reading the exhaust. If any of those three parts are malfunctioning you will get a reading that will trip the service engine light. That's why it's important to not assume that the catalytic converter is the problem. 

A mechanic will look at the sensors and look for signs of wear or corrosion. This can be a quick way to identify a problem that is cheap and easy to fix. If the sensors are in good condition, then other simple investigations can be done. For example, there may be a leak in the exhaust system before the catalytic converter. This means that more oxygen than normal will go past the first oxygen sensor, which can give an indication that something is wrong.

Know How To Identify A Bad Catalytic Converter

If there is a fear that the catalytic converter itself is bad, then a few issues will be looked at that can be easy indications. Clogs in the catalytic converter can happen due to engine oil or engine coolant that has gotten inside the catalytic converter. The part can also overheat and break down from rich fuel conditions, which are caused by another problem with the vehicle, which can range from a bad fuel injector to a damaged mass air sensor.  

For more information, contact a local company like The Brake Shop.