P0420

[TBFK]

Ok, so I put a pint of Seafoam in my gas tank when I filled it with 16 gallons, and 71 miles into the full tank, I got the code P0420. Has anyone else had this issue? What did you have to do to fix it?

[Legacy777]

It's a cat inefficiency code. I would suggest just going through the rest of the tank of gas, and then clear the code to see if it comes back. If you burnt a lot of carbon or other junk through the engine that may have tripped the code.

[TBFK]

Ok, I cleared the code and so far it hasn't came back yet, so so far so good. But I do need to replace my o2 sensors sometime soon, so I know that their good.