I was learning about PCV valve, when one of the online resources pointed out that the PCV valve will be closed during high engine load to prevent the lean-mixture (blow-by) in the crank case from entering the combustion chamber, as a lean mixture is not desirable during high engine load. But my basic automobile engineering textbook (local author) points out that during higher engine load, the blow-by increases and causes the crank case pressure to rise thereby increasing the opening of the PCV valve and letting more blow-by enter the combustion chamber.
Now I'm confused wether the valve actually closes or opens during high engine load.