2003 Ford Expedition Q&A

2003 Ford Expedition Question: where are the "rear O2 sensors located.

I can only find the ones forward of the exhaust Y. Those were replaced recently. -
Answer 1
Behind the catalytic converter. -
Answer 2
you should have 2 in frt of catt at y and 2 behind those on the upper side of the exh pipe,some are hard to see -