Crankcase ventilation system repair (PCV, CCV)

The crankcase ventilation system (PCV or CCV) controls crankcase pressure and routes blow-by gases back into the engine intake system. When this system fails it can cause increased oil consumption, unstable engine operation, vacuum leaks, mixture related fault codes, and a Check Engine light. Over time PCV valves, diaphragms, and ventilation hoses can wear out, crack, or become restricted with oil deposits. During service the system is inspected including valve operation, diaphragm condition, ventilation hoses, and possible vacuum leaks in the intake system. In real-world situations we at FIX SERVICE often see vehicles that already had repairs done elsewhere, and sometimes the problem is actually caused by newly installed parts that are incorrect or poor quality. This can include incorrect valve covers with integrated PCV systems or aftermarket crankcase ventilation valves that do not operate properly. In some cases a vehicle arrives with a Check Engine light after a recent repair, for example on certain Honda engines or commercial vehicles like the Mercedes-Benz Sprinter. For this reason proper diagnostics of the entire crankcase ventilation system is important to confirm that every component installed is working correctly.