Hey everyone,
After changing my oil last night, I was letting my car idle with the hood open and was just checking out my engine. I noticed that when I touched the far left (closest to the passenger side) spark plug wire, it was pulsing with every fire of that cylinder. It almost felt as if it was an air hose and giving rapid bursts of air. None of the other plug wires do this (although only two of them are accessible without removing the coil packs).

Is this common? Anyone else notice this? Is it possible that the wire isn't making a perfect connection somewhere?(perhaps it is arcing within the wire?)
I can't imagine many other reasons to "feel" it. And I know I am not just feeling the vibration from the engine...it is much stronger than that. That piston is still firing, too, because the engine is not running nearly so rough as it would be if it were only firing on three cylinders.

Input?

 

maybe the plug isn't screwed in all the way, and is jumping up and down on compression? i dunno. what year is it?

 

2001 ES--(i.e., 2.0 L engine)

I put the plugs in myself, and that was my first thought too. I know that they are all in equally tight (a little more than 1/4 turn past the plug becoming snug).

Josh