how to remove a stuck o2 sensor

Question

1. I have a code 0420, then I checked the pre-CAT O2 sensor that was bad with NO fluctuating signal but stayed low at 0.07V.
2. I tried to remove it but it seemed seized and I could only twist slightly, around 10 of 360 degrees.
3. How to safely remove this sucker without damaging the CAT threads?

Answer 1

There is a brand of lubrication called AeroKroil which loosens rusted nuts and bolts. I highly recommed that, it may be a little expensive but we use it for stuck sensors and it works more than 90% of the time

http://www.kanolabs.com/penLub.html