Cater liar convert or
It's difficult to buy a catalytic converter on your own. It's best to go to an auto parts store or find a mechanic with a good reputation using the Yelp app on your smartphone or tablet. A mechanic usually needs to see your vehicle in person in order to know exactly which catalytic converter to use. Some muffler shops are also experts in catalytic converters.
P0420 does NOT mean you need a catalytic converter...You MIGHT but, the other likely thing is the rear O2 (oxygen) sensor is no longer working properly. Other things could include exhaust leaks, damaged exhaust pipes, damaged O2 sensor wiring/connectors, etc.
Try rockauto.com but check your emissions decal. If it says "C.A.R.B Compliant" or "California Emissions Specifications" you have California Emissions and need the converter for that system. Otherwise you have Federal Emissions. HTH. -Jim
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