I guess the smell of burnt oil which I reported earlier had nothing to do with my CCV mod. I replaced the valve cover gasket a week before the CCV modification, I guess there's a light oil leak somewhere, not related to the CCV.

There's a guy on Youtube, Eric the Car Guy, who says that if your car burns a lot of oil and you do this CCV mod, the car will need a couple of hundred miles to burn off the remains of the oil that were in the intake and other parts. May be true as well.