I've been working on my O2 sensor for about an hour. Tried letting it cool, then tried warming up - can't get it to budge. My wrench was stripping so I got the actual O2 removal tool/socket. Still can't get it to budge.
Any ideas?

 

1. Penetrating oil several times over several hours.

2. Use a "T" handle socket wrench to get more even torque on the sensor.

3. Have someone tap on the socket with a hammer while you are trying to turn it.

4. Heat it again and repeat 2 and 3 above.

5. Impact wrench.

 

lol... WD40 should have been obvious, but I worried when it smoked. But that did end up working... also used a length of pipe on the T-wrench.
Thanks Monza!