In a message dated 2/3/02 2:47:30 PM, lamusicamellama@JUNO.COM writes:

<< There is play, I can move
tighten and loosen it within that 1/10 turn, but how to get it past that
point?  I've been using a crescent wrench, but now I think I'll go get a
fixed-size wrench.  Someone suggested heating up the area with a small
torch. >>

Les,

If you can move it, it is broken loose already so heating it is superfluous.
The starting threads of the sensor probably have a bunch of crap (rust,
built-up carbon, dried mucous, etc.) in them which is causing the sensor to
seize as you unwind it.  Just use a boxed end wrench or a cutaway socket and
wring it off.  The worst that can happen is you will strip the threads of the
sensor or manifold tapping or both.  At least you will be off the dime and
you can then deal with any additional complications.

Rich