Correct me if I'm misunderstanding, the 1990 TT has 4 points of crankcase ventilation. 2 PCV valves on the left and right valve covers. They way they work is when there is vacuum in the plenum they allow flow from the valve cover which obviously is connected to the crankcase, ok fine. Under boost they should be closed since we don't want boost pressure going into the crankcase so under boost they are not included as a vent. Next 2 items are the the hoses at the front of the motor coming off of the top of the valve covers and the vent to intake side of the turbo. Under boost they are not affected and since there is always vacuum on the side of the turbo even better. BUT they have a restrictor in each of them which is a metal round disk about a 1/4 inch thick with 1/8 inch hole drilled in it. So under boost when blow-by will be the most the only ventilation is through these 2 small 1/8 holes to vent the crankcase, If your running more boost than the stock PSI how is that enough ventilation? What's the deal enlighten me please.
Follow Ups
PCV system on TT how is it enough? - 300zulater09:45:16 05/08/22
09:45:16 05/08/22
