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Analysis of these O2 sensor graphs as they relate to P0420 (2005 Nissan Maxima)
I recently watched your YouTube video on P0420 and that was very interesting. I was impressed how you talked not only what the error code means but also how to check what exactly could be wrong with the car. I took a lot of inspiration from your video and tried to measure the O2 levels on my car. I don't have your tool but have a OBD2 tool and a Android app that graphs various sensors. Could you kindly tell me what you think could be wrong here. Do I really need to change the catalytic converted ? I am in California, so if I have to, it's going to be a huge bill.
In the video, I have the top row that contains O2 sensors: left upstream and right downstream.
Same for second row: Left is upstream O2 sensor and right is downstream.
I also have the rpm dial so that one can examine the engine rpm levels along with O2 sensor movements.
Thanks in advance. Hope to hear back from you guys. And please do keep uploading the videos. I watch them often even if I don't have any immediate car trouble. It's very satisfying to watch your work.
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