Can anyone tell me where the PCV valve is located on 98 ranger 4.0L 6cyl. ?

Driver side of engine. It's really low towards the bottom of engine. From where the #1 plug wire look between manifold plenum straight down and look for the hose. You will need a really long needle nose plier to reach the PCV and pull (hose and PCV) straight up. Once out remove PCV from hose and replace with new one. Reinsert PCV with hose attached back into hole.