Thanks Hellokit…I do have a multimeter and I will perform these tests before I condemn the sensor. I have a funny feeling the sensor itself is shot…I can purchase the proper sensor for under $100 and would probably save myself $200 by replacing it myself, and although the thing is rusted in there pretty good, at least part of the heat shield is broken and loose, so I may have a good chance of getting a wrench on it.