You unplugging the 02 sensor in the DP was responsible for the last two codes you got and possibly the missfire code aswell.
Not sure what made you go back to plugging the o2 pigtail back into the rear manifold location, we've been over that more than a few times now. Pull the damn 02 sensor from that rear manifold and plug it with a bung hole plug before it confuses you again.
you're confusing yourself and making problems , if your not comfortable with where things are routed yet take pics before you start unhooking wiring so stuff goes back where it's supposed to.
