I have a 2004 Kia Sedona with 125,000 miles. It threw the P0420 code about a year ago. I used some cataclean and had the code removed. And eventually the code came back up along with a P0431, so I had to park it. Im poor, I have more time than money so I started researching when I found your channel, and for 5 days I sat out with my van watching your videos and I was able to find the catalytic converter, all 4  oxygen sensors and so much more!! I've never been more entertained while being educated. 

I tried to do the repairs myself and was able to replace the O2 sensors properly!!! But after 7 days I had to wave the white flag. I didn't have enough tools, proper tools and im an older woman who hasn't worked on a car since the 80s. There's no cracking rusty bolts here .

I was confident enough in my new knowledge because of you that I took it to a new shop. They called me and mentioned having the transmission checked because it wasn't going over 20mph. BUT I knew what was wrong with it and it's never thrown transmission codes and with my knowledge, thanks again to you, the bank 2 catalytic converter has been replaced and with the O2 sensors my baby is scooting. Most importantly I didn't get ripped off. 

Thank you for your channel and for being you.. 

Thank you thank you!!