Just ran across Scotty Kilmer's P0420 "fix" which a lot of people claim to use. Run gas tank to 1/2 full ten pour 1 gal of lacquer thinner in and run 150mi at higher speeds or run at 2500rpm for 30mins.

What do you all think?

 

P0420 is a low cat efficiency code. The sensor is probably fine, the cat is dying of old age. The problem is the high mileage engine is starting to burn oil and burnt oil kills cats. The cat will slowly plug with oil ash over time until the the car will rebel with a plugged cat. Before converters the car would just smoke and burn oil, now they slowly die an expensive death. We must be saving the environment somehow with all of this. I cannot make a recommendation, it is entirely on you. My car has 280,000 miles and still has the original cat. My solution is to give the car to my 18 year old grandson and see how long it lasts. I remember what I did to my first couple cars, it won’t suffer too long.

 

That might work if the honeycomb in the converter is just dirty. But if it's deteriorated/breaking apart, nothing will fix it. Additionally, lacquer thinner attacks plastic and some types of rubber. Admittedly, the lacquer thinner is diluted by gasoline, but there's still a lot of plastic in modern automobiles. Scotty talks a good game, but I'm not convinced he is 'the' expert on everything automotive.

 

Thanks oldmarine. Much appreciated. Do you think it's worth trying a catalytic converter cleaner, something like Cataclean?

Did you by any chance read my other post by the same title? I thought I was adding the one you replied to as a reply to my original post to add some additional info. Wondering is the 2 codes are interrelated or if it's really 2 separate issues

 

Thanks oldmarine. Much appreciated. Have a 2Kmi RT I'm leaving for on Thu so I'm not sure I'll dig into this until I get back. If I have the time, I'll replace the t-stat.

P0420 - Catalyst system low efficiency. Thanks for the feedback

P013B-00 - Ho2S slow response lean to rich (sensor 2) Can this be related to the above? If not, should this be replaced? Is this upstream or down (in other words where is the location)?