After a very long conversation with three (idiots) VW dealers in my area
who tried to tell me I didn't know what I was talking about when I told
them that the sensor screws into the thermostat housing, I finally got
the part. I replaced the temp sensor and still had the problem ($40.00
if you by it at VW). If I unplug the O2 sensor it runs much better w/ a
good idle and it no longer blows black soot out of the exhaust ( you
need to hold a paper towel to the tail pipe to really notice it). Is
there another test (voltage, ohms) to check the O2 sensor without using
the CO test equipment in the bently manual.

The new O2 sensor would be $180.00 from VW or is there another company
who offers this at a better price.

Thanks for all the help,

Dana E Hager
Nazareth, PA

PS: Where did you find it for $15.00 ?