Spark plugs
 

I have a question,I replaced my plugs today,and my car has 125 k,I did one side at a time,and when I pulled the coils on drivers side first,took my flashlight to take a peak before I pulled the plugs out,and noticed the last 2 #4 & 6 pistons had a little oil at the bottom,then did other side and the same thing on spark plug #5 piston.it doesn’t use oil,smoke and don’t see any other issues,so where’s it coming from.

Most likely it's the valve cover gaskets, pretty common on the v6

Thanks,well been wanting to clean under the valve covers,so now I have a reason to pull it off.and go ahead and order a kit and replace gaskets and valve seals.

The plug valley seals are independent of the gasket, but they all come with the
kit.