Originally Posted by TboneZX3
There is a breather hose that runs from the intake to the cam cover.
I never even though of that
, I just assumed it was drawing from the cam cover TO the intake. Now, that I think about it, it just makes so much sense.
They call that hose the PCV hose so if the flow is from the main air filter to the intake and before the throttle body then the whole picture falls into place, they use the pressure differential across the throttle body for the source vacuum in the PCV system. Sweet, simple and reliable.
Now, if that purple thing is an actual valve then the entire system is completely explained. Duh, one stupid assumption had me flummoxed for weeks, I feel so stupid sometimes that it hurts.