One of the key problems with the Gen 1 B58 is the PCV system, which suffers with splits to the valve diagram. This causes smoke from the exhaust and often a strange screech from the top of the engine.

Replacement of the diaphragm is a simple task, with it being located under a cap on the rocker cover. There are many repair kits available too – however often aftermarket solutions do not have the quality required and so are not long lasting. For this reason, we sell and fit ONLY the Genuine BMW Parts kit.

Part no19 in pictured diagram – BMW part number 11121025447.