oil samueljo

I have a 2004 chrysler pt cruiser 4 cylinder b 2.4L WHEN YOU PULL UP THE SPARK PLUG WIRE OIL IS COVERING THE SPARK PLUG AND OIL IS RUN DOWN FROM THE TOP OF THE VALE COVER TO SIDE OF THE MOTOR AND IS BURNING OFF THE EXHAUST COVER PLATE.WHAT IS CAUSING THIS TO HAPPEN. SAMUELJO.