A few days ago the check engine light came on and it read p0138, bank 1 sensor 2, so I replaced the #2 O2 sensor. When I went to erase the code, it read that there is now an error on P2195, which is bank 1 sensor 1. Is it even possible that both sensors went at the same time, with only 37,000 miles on the truck, or are the electrical gremlins beginning to stalk me? Any ideas?