Yes, Klaus, you are correct. (the reason it is so cheap is because I have a friend that runs the code at the dealership)I called him and he told me what the head mechanic said at the Volvo dealership.(I hope this helps someone) If you are getting bank 1 and bank 2 codes, then it is going to be your MAFS (mass air flow sensor), but if you are getting only ONE of the banks reading as a problemed area, as a rule of thumb, it is more than likely the O2 sensor that read out that is bad. I found brand new front Bosch O2 sensors on ebay for about $85 a piece. I will wright back in and tell if this works or not. If it does, someone else that has O2 problems can pinpoint via this comment. Thanks guys!