What these units do is keeps the engine from sucking in oil and gas vapor directly into your intake causing a drop in Octane and sludge build up. The short version of the PCV job is to take air in from the cold air intake and run it into the drivers side PCV it then circulates around and exits the engine on the passanger side. From there it goes directly into the manifold to be re burned as an emissions requirement. Sounds fine unit is starts sucking oil into the manifold! This picture/diagram is the drivers side one that is why the air going into the engine is filtered right before it goes in. The JLT unit for the passanger side (and the only one you REALLY need) is the opposite. The vapor/oil is strained through the filter
FIRST then the claen air with vapor goes into the intake maniolf to be burned off. The filter catches the oil and lets it slowly drain into the canister to be removed later. Let me tell you these things work!!! I catch 1/8" worth in 500 miles which goes back into the engine!