The car in question is a 98 S500 sdn w/ 65k. I bought the car about a month ago and when I checked the oil it seemed to be overfilled (i.e. the oil level on the dip stick was about 3/8 to 1/2 inch above the max line). The next morning I set out to drain some oil to get to the correct amount. So I took off the oil fill cap to siphon some oil out with an old turkey baster. However, before I began to siphon the oil I decided to check the oil again and got a reading that was fine (right at the max line). I figured I would drive around for 20 minutes to warm the engine and see if the reading was still high before I started draining the oil. That seemed fine, until I was driving for about 15 minutes and there was smoke coming from under the hood. The smacked ass that I am, I forgot to put the oil cap back on, so oil spilled all over the engine bay! What a fool!

Anyway, since then (three weeks) I changed the oil and the car has been running fine. Yesterday, I decided to change the plugs and when I took off the black cover that houses the coil and sparkplug, I noticed that there was some oil in there. I cleaned that up and began to change the plugs. When I took off the coil to get to the plug, there was a considerable amount of oil in the sparkplug well (put it this way, there was enough oil to cover the entire spark plug socket). I unscrewed the plug and cleaned out the well. This oil was in each of the 4 plug wells on the same side as the oil fill cap (passenger side).

My Questions:
1) Could the oil have gotten in there from me leaving the cap off? My guess is yes.

2) When I took the plugs out, there was oil all over them, including the tip where the spark is made. For oil to be covering the tip, that would mean that there was a big problem, a cylinder was leaking oil (or 4 cylinders since all four plugs had oil), correct? I am just uncertain if the tip of the plug was just oil filled from when I pulled it out, or if there is a leak. My guess, is that it was covered in oil from when I pulled it out b/c if there was oil where the plug makes the spark, the car would have been running like **** and smoke would have been everywhere, correct?

Everyone's help would be greatly appreciated. Hopefully, this is just a non-issue and will be resolved inexpensively.

Feel free to laugh or mock me for leaving the cap off, I deserve it, but only if you give me some insight to my questions.

Thanks