Wow, that can be a tuff one.
My first choice; ox-ace heat, followed by the wrench
Another option that was said to me was try to tighten first, then back out.
This tip was from a old master tech that teaches tech courses. Now I tried
it once and it didn't work for me, but we still try (I think I used heat on
He also said ATf is a good penetrate. get the part hot and pun some on it
and let it set overnight, the dissipating heat will wick it into the
I also have in my box a tap that is the 02 sensor size, wasn't easy to find,
but I ordered it before I needed it.
There also is an heli-coil set for thread repairs, sometimes they screw
themselves up on the way out
If you remove the manifold you could carry it to a vise or a machine shop.
Heat is always the best choice.
Stephen W. Hansen
ASE Certified Master Automobile Technician
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