I have a slight weird issue. Tried to search this problem but non of them come up as an issue after cat replacement.

So heres whats going on. I had a misfire on Cyl 1 changed all the Spark Plugs then the misfire was there but now on Cyl 3, change the ignition coil and the problem went away.
I had the shaking going on for a few month and that had caused the Cat to get clogged so i had a muffler shop replace right side cat front and rear. Now the is okay after driving about 30 Miles the CEL came on i checked the code and this is what i get (shown in screenshot link below)


Is the Cat bad or is it something else can that be causing the issue.
The RPM from a cold start is around 1100 and once it get a tad bit hot it slowly goes down to
660ish, if i hit the gas pedal and make it go to 1500RPM it goes back to resting position at 660ish.

History about my car
2005 Xterra SE
141k Miles
Everything is stock on the car

Let me know if there is addition information i need to provide.

Thank you
2005 Xterra SE
2 Wheel Drive