2001 Ford Windstar Oil In Throttle Body

My 2001 Ford Windstar Has 36,000 Miles On It. I Am Getting Oil In Throttle Body. It Has Updated Left Valve Cover. I Have Changed Pcv Valve. Oil Is Dripping Out Of Pcv Hose At Throttle Body And Is Puddleling In Throttle Body. Van Is Running Good, But Idle Does Surge In Neutral Or In Gear At Times. Dealer Has No Clue, Any Ideas?