OK, I am worried that I may have something serious here. I just bought this 02 4.6 with 67,000 miles. I decided to go ahead and change the plugs, NGK iridium. Seemed to be a plug of choice around here and had great results with my 97 mustang. The noises these plugs made coming out was a little scary. Squeaking and what not.
When I removed the driver side rear plug it had oil all over it.

Didn't seem to be on the porcelain or tip of the plug, but the thread area/ metal part. After I put the new plug in I noticed the coil pack was different than the others as well. Its hard to see in the pic, but it is date stamp 12/07/08.
I know this can't be good, but how bad is this? Repair wise?
The passenger side rear plug had some oil on it as well, not as much but still oil on the plug. Here is a pic with the plug out on the passenger side.
Here is a link to another thread I started with some vids of the engine running and the exhaust. Seems maybe this oil on the plugs issue may be the culprit.
http://www.xoutpost.com/x5-e53-forum/...questions.html
Any idea what is causing this leak? The X seems to have plenty of power.