My check engine light came on a while back and I already knew it was the sensor because I put an x-pipe on with no MIL eliminators. I installed the steeda plug-in eliminators and the light went away........for a while. It's back on so I went to autozone for them to use the diagnostic gadget, and it said P0153 bank 2 sensor 1. What's the deal? Do the MIL's not work or what?