Of late my 2000 4Runner has been making some rattling exhaust noises. I figured it was a heatshield or something else non critical on the exhaust system and I hadn't gotten around to checking what might be causing it.
So yesterday I'm driving to work and the exhaust gets noticeably louder. I get to work and poke my head under to see the secondary O2 sensor flange empty and the O2 sensor hanging by the wires.
Looks like the nuts rusted off since the studs and sensor look just fine. I tied the sensor up with cable ties before I left work at the end of the day and drove home.
What surprised me is this - No check engine light. I have to wonder what the point is if the sensor can be tricked so easily, just by having it sit in clean air...
So yesterday I'm driving to work and the exhaust gets noticeably louder. I get to work and poke my head under to see the secondary O2 sensor flange empty and the O2 sensor hanging by the wires.
Looks like the nuts rusted off since the studs and sensor look just fine. I tied the sensor up with cable ties before I left work at the end of the day and drove home.
What surprised me is this - No check engine light. I have to wonder what the point is if the sensor can be tricked so easily, just by having it sit in clean air...
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