BMW N54 Upgraded PCV Valve Kit

This upgraded PCV valve kit fits all BMW N54 valve covers.

The PCV check valve in the valve cover is supposed to vent oil vapor from the valve cover. The weak plastic on the original part never seals well and liquid oil and vapor is allowed to escape the valve cover and run into the intake manifold instead of returning to the oil pan. This liquid oil settles on the intake valves or is burned up in the engine (neither of which is good). Additional boost, such as from tuning or better turbos, also forces more oil past the check valve. This upgrade is a 1-for-1 replacement to the original but keeps the factory vent system in place.

This upgraded oil check valve and cover is made from machined aluminum and is much stronger than the original plastic. It seals better and will not fail like all of the original ones do. No matter what other crankcase vent upgrades you make (oil catch can or vent-to-atmosphere), if you're using the stock valve cover you need this PCV check valve.