I have oil leaking out of my "coil covers" - the covers that bolt in over the coils and spark plug holes. The leak is obviously coming from a crack at the bolt (probably overtightened), so I've ordered replacement covers; my question is: why/how is oil getting into this area in the first place? I'm almost afraid to find out, as the car currently runs excellent.

 

forgot to mention - it's a supercharged engine (98 XJR)....

 

OK, which side is it? If it is on drivers side, possibly coming from the oil filler cap. It has an O-ring that over time will leak. If you see any clumping dirt or oil around there I would start by replacing that.
There is no way for oil to leak from that coil cover unless the cam cover is cracked. Leave the coil cover off, clean the area and run vehicle at about 3000 rpm for a couple of minutes and see where it is coming from.

 

thanks.... it's coming from the passenger side. I don't know if this helps, but last time I changed the spark plugs, some of the holes on that side had a bit of oil in them. I'll try what you suggested.

 

if you had oil on the plugs, you need to replace the cam cover gaskets. When you do that, it will come with the new spark plug boss seals. That should solve your problem.

 

That makes sense - many thanks!!

 

Very welcome.