I saw these claimed o2 sims on ebay, they look just like spark plug non-foulers, and when screwed into your o2 bung and then screw the o2 sensor into it, it'll eliminate the p0420 code, has anyone seen or tried this before?

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looks like it could work. i wouldnt mind tryin them out. plus they are cheap so you cant lose really. im thinking, by positioning the 02 sensor a little out of the exhaust pipe, it would be just enough to keep the unfiltered exhaust from triggering the code.