It could take a complete drive cycle for the code to set again.

Shock the threaded connection; whether mechanically (hit the wrench with a hammer) and/or thermally (heat it up real hot then spray it with some water or penetrating oil to cool it down fast) to break it loose.

 

Any tips on getting this sensor off? I keep spraying with wd40 and letting it sit. Back and forth and this stupid thing will not budge.

 

I edited my post to include that information so as not to double post.

 

This rusted bolt will just not move. My hands are throbbing and red and it just will not budge. For the last 2 hours i've been trying to get this thing to move and it's gotten me nowhere. This is seriously going to drive me nuts.

 

If you have a blunt nosed punch, you could try hitting the bung that is welded into the exhaust to try and shock the joint.

 

So I switched out the O2 sensor and cleared the codes. It took about 3 hours to break that rusted sensor loose, but I finally got it.

Drove about 40 miles and now I'm getting p0420 (Catalyst System Efficiency Below Threshold Bank 1). The person I bought the car from said the cat was gutted. I guess, now I know for sure that it actually was.

 

So you aren't getting the heater code anymore? Might have just been a connection issue then.

 

No more p0141 heater code. I replaced bank 1 sensor 2, cleared the codes, drove about 50 miles, and now I'm getting p0420 and that's it.

 

Oh ok. By "switched out" I thought you meant swapping B1S2 & B1S3.

 

Nope... i bought a new 02 sensor and just put it in. No more p0141 code now. I spent over 3 hours getting B1S2 out. I don't know if I could have handled doing that all over again with B1S3.

So i guess now I'll need to put in a new cat to pass emissions and get rid of this code. Any recommendations?