This oil separator is a direct fit replacement component manufactured to original equipment specifications for BMW models equipped with N52 and N53 series engines. As an integral part of the crankcase ventilation system, it separates oil mist from the blow-by gases generated during engine combustion, returning liquid oil to the sump while directing purified vapours back into the intake manifold for reburning. Constructed from high grade engineering plastic with integrated sealing elements, this separator offers excellent resistance to thermal cycling, oil contamination, and chemical degradation. The precision moulded inlet and outlet ports match the factory hose routing exactly, ensuring a leak proof connection when installed with original clamps and gaskets. This oil separator is compatible with BMW 1 Series E81 E82 E87 E88, 3 Series E90 E91 E92 E93, 5 Series E60 E61, 7 Series E65, X1 E84, X3 E83 E84, and Z4 E85 E89 models produced between 2004 and 2015, covering 323i, 325i, 328i, 330i, 525i, 528i, 530i, and X3 xDrive25i variants. Common failure symptoms include increased oil consumption, excessive blue exhaust smoke, rough idle, a howling noise from the valve cover, and illuminated check engine lights; replacing with our unit restores proper crankcase pressure regulation, reduces emissions, and prevents sludge buildup in the intake system. Every component undergoes 100 percent leak testing and dimensional verification prior to dispatch. The material meets OEM temperature and pressure standards, ensuring long term reliability under harsh under bonnet conditions. Backed by a 24 month warranty against manufacturing defects, this oil separator offers workshops and individual owners a durable, cost effective solution that maintains your BMW’s engine performance and extends service life. Installation is straightforward with basic hand tools and is ideal for routine crankcase ventilation system maintenance or valve cover gasket replacement.