So my check engine light came on, had a p0133, o2 sesor 1, bank 1 slow to respond. I hooked up the IDS to my car, pulled up the pid and verified slow switching. I replaced the sensor, and all is good. Only problem is, I replaced the same sensor about 15,000 miles ago for the same issue. I know if the sesor gets contaminated with oil or coolant it can cause it to go bad, so today I pulled out my plugs to check them. For 38,000 miles, they looked pretty damn good. The back 2 plugs on both sides of the engine where a little white, but nothing severe, nothing that would make me think twice about putting them back in. (plugs are SUPPOSED to be good for 100k). Any suggestions as to what might be goin on? Or is it just bad luck with 02 sensors?