I've got a 92 Taurus 3.8 GL and I'm getting an oxygen sensor fault on it. I figured they'd probably never been changed and decided to change them, I've found conflicting numbers of downstream O2 sensors so I decided to get under it and check how many it had. I can't seem to find any. I looked all around the cats and and all the way down to the muffler, there didn't seem to be anything. Can anyone let me know where they are if it has any? By the way, I'm in California if that matters, I know there's a lot of different smog stuff here.