I've been getting the P0420 code on my Hyundai Accent(159k miles) it comes and goes on it's own, especially after some hard driving where the check engine light will go out. So I've decided to try and clean the cat.
I monitor the O2 voltage and you can see it does not work like a new one as it will more closely follow the primary 02 voltage rather than stay high like it should when cruising.
I took the primary O2 out. The cat hangs vertical. Then poured 2L of lacquer cleaner through it. Put O2 back in and then after a couple hours poured another L of the thinner.
My plan now is to let it sit overnight, then take the O2 out again and let it sit another 24 hours. Then put it back together, start it up and hope I don't blowout the cats and muffler......
I monitor the O2 voltage and you can see it does not work like a new one as it will more closely follow the primary 02 voltage rather than stay high like it should when cruising.
I took the primary O2 out. The cat hangs vertical. Then poured 2L of lacquer cleaner through it. Put O2 back in and then after a couple hours poured another L of the thinner.
My plan now is to let it sit overnight, then take the O2 out again and let it sit another 24 hours. Then put it back together, start it up and hope I don't blowout the cats and muffler......