Quote Originally Posted by koukis14
did you have it plugged in when you screwed it in?
Of course not, that makes it even harder to do. Plus I didnt screw this one in. Who ever worked on the car last\ factory (doubtful) were the ones who cross thread that bitch.

I have the new O2 sensor installed and the loud ass lawnmower noise is gone. The new O2 threaded very smooth and nicely into my newly installed cat-less header.

I am glad I ran into this while upgrading to a performance header rather than my O2 sensor dying on me. I would have had to go out and buy a new header because the xthreaded O2 sensor took all the thread on the stock header with it...