Hey guys, I have had a little trouble replacing my 2nd oxygen sensor... actually its the removal I'm having issue with. First I tried just wrenching it, no luck. Then I bought an oxygen sensor wrench to use with a ratchet, still no luck. Tried soaking the threads with PB Blaster and hitting the wrench with a hammer to turn it counter clock wise but it wont budge at all. Has anyone else had trouble getting this off or any suggestions?

they make special o2 sensor deep impact sockets

Cheater bars are your friend, also you can melt a crayon into the threads to bust it loose. Works decently but makes a hell of a mess. Also Im not sure how great of a idea the crayon is with a sensor.

heat the pipe and sensor up, it'll ruin the sensor but you're replacing it anyways.

ended up having to take it to a shop, they had to remove the radiator and cut the sensor in half.... then drill it out. that thing was tough.