oil catch can purpose
Posts: 659. RE: Oil Catch Can: Its Purpose. the pcv is on top of the valve cover and releases oil that blows past the internals under high boost situations. all it does is release the oil to get it out of the engine.here are 2 locations for a catch can-on the PCV side and on the crank case vent. On the PCV side it will prevent oil from entering the intake manifold right in front of the throttle body. This can will prevent oil from going into your cylinders causing carbon fouled plugs and depsoits.