We’ve been around BMWs and MINIs for a while, and have come to an understanding that BMW just can’t seem to make a properly functioning and reliable PCV (Positive Crankcase Ventilation) system. They either pass too much oil vapor, clog, rupture check valves or just do a poor job in the first place. The twin-turbo N54 engine (as used in the 335i, 535i, Z4 3.5i, X5 3.5i, etc.) is no exception. The oil vapor separation is poor, causing the need for walnut blasting of the intake ports and valves (see our DIY Video on this task, HERE) and the PCV check valve is weak in sealing under boost pressure …. and, before too long, fails to seal under normal pressures, resulting in boost pressure being applied to the engine’s crankcase. This is “not good”. At the least, this can increase oil consumption past the piston rings and valve guides, in addition to creating (or increasing) external oil leaks at the valve cover, oil filter housing, crankshaft seals, etc.
Replacing a weak or faulty PCV check valve requires that the complete valve cover be replaced. The valve cannot be replaced separately. And, if replacing the valve cover, you still get the weak original valve.
The FTP Motorsports upgraded PCV valve, for the BMW N54 turbo engines, prevents turbocharger boost pressure from being forced back into the engine’s crankcase. The FTP PCV valve replaces the factory valve and is much stronger, to seal under high boost. Additionally, it seals better, at all times, than the factory valve. As noted above, the original valve is not replaceable on its own. The complete valve cover must be replaced. Therefore, the FTP upgrade valve can be looked at as a repair piece for a worn-out original valve, as well as a performance upgrade to keep all of your boost where it should be …. in the intake, NOT in the crankcase.
The valve includes full instructions and can be installed without removing the valve cover.