I'm throwing a PO420 code on my 2011 chevy equinox 2.4L. Same as this post on this site: https://www.autopartsforum.com/topic...4l-p0420-code/ and it sometimes feels like it doesn't have full power. I'm thinking maybe bad cat and when i login to my chevrolet i do have all these added special coverages. I'm thinking of taking it to the dealer, however I do have access to a scanner that I pulled the code with, so besides checking O2 operation, is there something to look for to identify a bad cat using the scan tool and maybe some sort of back pressure test? These are the special coverages added: