When fighting a tough O2 sensor, I have found that special O2 sockets are
too weak because of the slot for the wire.  A stout box wrench is best if
the connector is small enough to fit thru it.  Of course if you are cutting
the cable off anyway, that doesn't matter.
  Recently I had one where I had to put the cat in a big vise, heat the
bung red hot, and use a box wrench with a pipe extension.  Probably would
have damaged the element inside the cat, except that it had already
disintegrated and been disposed of.  I just wanted to prove to my self that
I could get the remains of the sensor out.
  What fun,
Larry A.

On Fri, Oct 2, 2015 at 9:43 AM, Richard Koller <brvkoller@gmail.com> wrote:

> Dennis,
> I had this same problem and I heated the cat at the junction where the O2
> sensor screws in with MAPP gas. Then quickly slipped my 22mm box end over
> the disconnected sensor wires and was able to break it free. It would be
> better as others have said to use the dedicated O2 sensor socket. Heat was
> essential however in my case.
> Good luck.
> Rick Koller
>
> On Thu, Oct 1, 2015 at 12:37 PM, Dennis Jowell <dennisjowell@gmail.com>
> wrote:
>
> > I just started to replace my O2 sensor on my 2.2 wbx. No,luck using my
> > wrenches . Everything is rusted together. The catalytic converter is only
> > about a year old. Is there a better way to remove the sensor? Should I
> use
> > my touch to heat the sensor ? Any ideas would be great. I might get to
> > Quebec yet just have to get this done.
> >
> > Regards,
> > Dennis
> >
> > Dennis Jowell
> > Scotch Hollow Farm
> > Newbury, Vermont
> >
>