Unused sensors on 4.7 question?

From : mark

Q: folks i have a 2000 dak quad cab 4x4 w/ manual transmission and was changing the plugs recently and noticed 2 sensors connected via the hold downs for the plug/coil assembly on the second plug set back from the front of the engine. i assume these may be temperature sensors since they the are connected via a screw to the head. what is odd is that there are no wires attached to either of these alleged sensors. there appears to be a single jack on each that could accept 1 wire. does anyone know what these are and why dodge would include them on an engine w/o attaching any wires to them thanks .