Ok.....


The first code is an o2 sensor code for the o2 sensor that controls the fueling of the car. You either have cut wires or it's bad. That's the only 2 things it could be.


Yes they do make an 02 sensor deleate for the rear sensor. Do NOT use one for the front.


The o2 in the front is likely the cause for the way it has been driving and the performance loss you have felt.