Well if you have an 02 sensor code probably heater circuit then there's a good chance you need a new 02 sensor.

Next, your lean codes and now random misfire codes are pointing in the direction of a vacuum leak or bad maf.

Coil packs usually don't fail 3 at a time. 1, yea I can believe it. Also check to see if the spark plugs on that bank aren't filled with oil from a leaking valve cover seal.