To prove for yourself if you're making any progress cleaning the crankcase ventilation system by using B-12 in the large hose on the left side of the engine or not.
Since we cannot see the cleaning, this is one way to prove what you are doing is doing good for your engine.
Clean-operation of the PCV system helps keep costly parts safe from water/condensation damage and rust. The Variable Cam timing controller is susceptible to water and it can stick in one position and create runnability problems.
