on my 2004 5.4 I have removed my right cylinder head for replacement. There is a sensor on this head beneath the intake manifold. When removing the sensor I turned the plastic connector about 1/4 turn or less prior to turning the actual sensor. What sensor is this and would I have broken it by this mistake? It did not make a sound, it just turned a little on the base of the sensor.

 

Without a pic, I can guess it is the cylinder head temperature sensor. And yes you did damage it if the plastic rotated. If it is the temp sensor, it cannot be changed without the removal of the intake manifold.