New catalyst, still P420 code

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Joined: Sat Jun 07, 2014 5:42 pm
Car: 2007 G35 sedan (journey)

New catalyst, still P420 code

Postby tjrob2000 » Wed Oct 07, 2020 5:25 pm

2007 G35 Journey, 212,xxx miles. I recently had the P420 code come up so I ordered a new cat plus all 4 O2 sensors. I'm still getting the P420 code. I checked the O2 sensor voltages using a BlueDriver code reader and it shows the bank 1 sensor voltage is lower than sensor 2. Sensor 1 voltage is in the .45v range while sensor 2 is in the .78v range. Bank 2 sensors are behaving normally with sensor 1 at .8v and sensor 2 around .4v. Anyone seen the strange behavior I'm seeing on bank 1?


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