is a piston not firing?

my spark plug #3 looks like it bounces up and down and when i touch it, surly i feel it going up and down. my engine makes a weird noise and i think these two are related. any comments/suggestions ?

did you try tightening it?

one of my friends had a spark plug come up on his sunbird (yeah i know… sunbird… lol). anyways it turned out the thread was screwed on the head.
that’s worst case scenario i would think… it may have just come loose.