This BMW B58 PCV Diaphragm replacement cap comes with all the necessary hardware to replace your old or leaking PCV Diaphragm cap.
The BMW B58 PCV cap is prone to failure with vehicle aging and mileage, as the rubber portion of the PCV cap will naturally dry and begin to crack over time. The PCV diaphragm cap is subjected to constant negative pressure, as a result, any cracks or leaks in the rubber seal will cause engine malfunctions. A replacement plastic end cap is also included in this kit, as it is not uncommon for this portion to be damaged upon removal.