Bad cats?

http://www.raimotorsport.com/Threaded-J-Pipe-with-Gas-Flow-Inserts-for-CEL-prev-p/11619vib.htm
Problem solved using these on my 09. Been a few years now.

 

I had a p0420 code. It turned out to be the donut gasket on the passenger side that connects to the Y pipe. I just saw a little bit of carbon where the leak was.
There was no play, had to break both sides to replace the one. Took about an hour to replace both.

 

How do this actually work? It's it limiting the amount of flow the sensor picks up?

 

I'm going to climb under it in the morning and give it a good look over . By the time I got home today it was already dark And the truck was hot . Did manage to change the oil. Prick who did it last tightened or installed it dry.

 

Yes and yes.

 

I changed my downstream one today .and the plugs . Dang spark plugs were bad. I have a feeling they are the factory plugs .when I fired up the truck it sounded so much better .

 

Hello everyone. Thank you for your comments. I have replaced all the 02 sensors, cleaned the MAF sensor,changed the spark plugs,oil,transmission oil,and I still had p0420 code so I asked about the cataclean. Strummer you replied that it did not work. I didnt try it. I went to Autozone and this very friendly employee told me to get this product from Lucus oil.

 

I have 198,755 miles on my 05 tacoma. The engine light is off! Since Sunday. I dont know if it will come back on but so far its off. Wanted to share the info.

 

It didn't work for me. I think mine was the o2 sensor and plugs . Plugs were bad bad shape. After I did that I have drove close the 400 miles with no codes

 

Will look for some and run it too . Can't hurt nothing

 

Well since your codes went off you might want to wait a little before you add more chemicals to your tank considering you put thinner and cat cleaner already. Im glad the spark plug change helped.

 

I am having the same issue and been years now but luckily i dont have emission testing where i live and i can not notice any lack of power and our family friend/mechanic said not to worry. I am starting to work on my truck more and more as money gets thin and i want to learn more and i want to try and do what you just listed above. can you post or PM me how you replaced the o2 sensor and cleaned the MAF. just a newbe looking to fix his own truck. thanks

 

i think Cataclean is only a temporary fix to get thru State Inspection

 

Cat clean for me only kept the codes off for a couple of weeks but the lights came back

 

Urd y pipe. Deletes the rear cats. Use your O2 sensors and your done. The cats don't get monitored.