nov 15, 2019 · chevrolet cruze eco is down again because of a p0171 engine code. Attributed to a failed pcv system. This video walks through the ultimate fix to the. this condition may be caused by a missing non return valve. ⇒ increased crankcase pressure can force the oil into the induction system and eventually into the cylinders. aug 22, 2016 · pcv gas at the intake manifold check valve flows into the intake manifold but not back into the pcv system, and air at the turbo inlet housing flows into the turbo.
