There is no factory separator on the Explorer, which is unfortunate as you can see. All those 2.3L Ecoboosts sucking oil into the intake and ending up on the valve's!
This is installed on the PVC, so "dirty side".
Every Ecoboost has some form of oil separator, including the Explorer. The design has changed over the years, but they are still there. The Mustang even has an upgraded 'track only' part.
2.3L MUSTANG ECOBOOST OIL-AIR SEPARATOR LH
2.3L MUSTANG ECOBOOST OIL-AIR SEPARATOR LH|Ford Performance Parts
