Hey everyone, my CEL is on for code 21, main o2 sensor, I have a universal o2 here, and when I got under the car I had trouble seeing how to remove the sensor right after the cats. So, right under the driver side mirror is where I'm at.
I notice its a bolt type, just unscrews, but the wire appears to go up into the car chassis via some rubber lining. HOW do you get to the harness clips, and just remove the o2 sensor. Also, does code 21 mean the driver side main o2 sensor? Thanks.

 

21 is main... Harness clip/connector you just pinch it and pull or pull one of the tab that locks it in place then pull out.

 

theres also a special socket for removing o2 sensors if yours is really stuck on there.
a trick i learnt if your o2 sensor wont come off even with a breaker is to drive the car till its warm/hot, turn it off and give it a shot when its still hot. for some reason it comes out easier but obviously you need to be careful not to burn your self. once you break it loose you can let the car cool down and come back to it later.

 

Thanks a lot boys, I appreciate it.