I just replaced the Bank 2, upper CO2 sensor on my car. This has made a tremendous difference in the car. I ran it for about a half an hour without any problems. She idles like a dream without a CEL. If the P0420 code comes back I may try Berryman's B12 or the mileliminators. Oh by the way, you dont need an O2 socket for this fix, just a long handle 7/8" wrench. And YES, it can be done from underneath the car. This was the easiest way, taking only about 35 mins. If you had the oil filter off while changing the oil, this would make for some extra room. All in all, very easy and painless fix. Thanks guys!
