O2 sensor CEL codes only mean value being reported back by the sensors is not in correct range. Period. End of Story.
Issue COULD be A sensor, though rarely does more than one sensor go bad at same time let alone on opposite banks (unless fouled by something further upstream). You start by checking the wiring to the sensor and then testing sensor itself w/ a multimeter. Proceed from there but otherwise blindly throwing a couple hundred $ at the sensors is frankly plain foolish.
Good luck
PS - Most natl auto parts stores/chains will read codes for free
