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Q: P0420 P0430 trouble codes

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I recently changed out the o2 sensors in my car do go an oil leak that also got into the exhaust but I didn't drive it for more than a few miles due to the fact it was smoking so I fixed the leak and changed the o2 sensors and if fixed that problem but not the P0420 and P0430 codes are coming up do u think it could be the sensors I used (universal ones) or maybe I did some thing wrong or is it because of the oil got into the exhaust and clogged the catalytic converters

My car has 150000 miles.
My car has an automatic transmission.

A: Hello. Thanks for writing in. The universal...

Hello. Thanks for writing in. The universal oxygen sensors, a bad connection, or a bad catalytic converter can all be the cause of the codes. If you can you access to a known good oxygen sensor and test it in the vehicle, then you can rule out that as an option. Universal oxygen sensors are fairly new to the market and may have faults. You will also want to check the connection to the sensors to make sure they are clean, dry, and tight. If the oxygen sensors have been proven to be ok, then you are likely looking at a bad catalytic converter. You should test the oxygen sensors and the connections first before resorting to inspecting the catalytic converter.

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