Don't take the parts monkey word for it. Post the codes & let us help you be a bit more certain of what needs to be done with your car. I have had my CEL come on 4 times. Only one time was I required to replace a sensor.
Additionally, Bank 1 is the fire wall side. The lower (downstream) sensor is easy. The upper (upstream) sensor is a pain. At least is was for me. Maybe my approach was wrong, but I had to remove the Y pipe to get at it, & even then access was VERY limited.
