if the sensor  originally had some anitseaze compound applied they
usually will screw out with a little  effort.  if the compound was
never applied  get some real heavy duty rust remover compound and soak
it   good.  apply heat, and if your religious, a few prayers.
jimt
On Saturday, Sep 28, 2002, at 18:45 America/Denver, Ki wrote:
> pulled the cat out but can't seem to unscrew the o2 sensor off the cat.
> does it just screw right off?  am i better off just getting a new 02
> sensor?