As outlined in this thread:
I had a recent misfire issue. Unfortunately the dealer has been unable to find the source. Since the original misfire I can feel the car vibrating when I am in drive or reverse and am stopped with the brake applied (ex - waiting at a stop light). It goes away when I drive and when I am in neutral. I realize there is SOME vibration noticeable in gear, possibly because of the way the engine is mounted. However, this seems different.
The tach stays at 750 rpm in idle (it may fluctuate a TINY bit but never goes over 800 at idle) as always. The vibration feels much like a vibration one would feel if a cell phone or pager were left on vibrate. This doesn't seem to be a rough idle where the car is "jittery" or "jerks", and, as mentioned, the rpm doesn't change.
I would think a bad coilpack or plug (plugs changed at 40K, Im now at 45k) would cause a misfire, and a CEL. I've looked into a throttle body cleaning and will do this, but I would think that would cause a rough idle as well. My understanding is that a MAF problem would be similar.
The only thing I can think of is a motor or tranny mount issue, but the car only has 45k miles and this problem was non existent until the misfire. Im almost certain it isn't related to having the car lowered recently.