I think I found it. It is not located on the cylinder head anywhere but connected to the thermostat housing just like the other 2 sensors. It is connected kind of parallel to the ground at the right side (looking from the front of the car) of the thermostat housing. I just can't figure out how to remove it for sure. I guess you just pull it straight off, but it's on pretty tight...

ryan

__________________
RG Newell

1984 300D
1972 250
1986 560SL
1991 300CE