Question about 2000 Mazda MX-5 Miata

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2000 Mazda Miata, check engine light comes on. Code PO420

Had local auto parts store scan code and they came up with PO420. I just bought this car. Seem to run good. Have the 2000 Miata had any problem areas that you know of that would cause this problem?

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The P0420 code is a more common one in general. The description for P0420 is Catalyst System Efficiency Below Threshold (Bank 1). You're going to want to focus your diagnosis efforts on the O2 sensors, catalytic converter, and exhaust system. Here's a great detailed article on that specific code and how to fix it -

Posted on Dec 15, 2008


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