These engine are known to leak oil. I have a 2003 3.0L. They can leak from the oil pan and crank seal, easiest to fix. They can leak from the valve covers and the timing cover(hardest to fix). The pan is aluminum and has the grid design, that is where the oil seems to wind up when the leak is from up top. The valve cover gaskets become hard and when the oil starts slinging off the timing chains as the engine runs it gets past the hard gaskets. The upper intake has to come off to replace the valve cover gaskets. If the spark plugs have not been changed now would be a good time. With time the upper intake gaskets develop vacuum leaks, so replacing the intake gaskets no bad anyway. This effects the MPG more than idle. The timing cover is the tough one, 6-7 hrs labor.
If you need spark plugs and go the extra with the valve covers you may get the oil leak.