so run a hose from breather to catch can and not let catch can breathe? sorry if im taking you up wrong but if thats the cases then all your doing is bunging up that breather in theory keeping the excess pressure in the crack case.. do explain if im taking you up wrong tho, i just think we are not on the same page.. im not on about the PCV, im on about the other breather @rbz, ive very rarely seen a catch can full of oil, in fact, the only time i came across that it was half full but that engine had problems but even at that it took months to fill that much ... oil wont pour out that breather, its only residue and vapours.. if theres alot coming out, theres underlining problems with your engine so your engine is healthy... guys ive owned my glanza years and have worked on these cars for much longer... its actually what i specialise in.... heres just one example and this car is taken care of by no other than chris carson.. if it was wrong, he would change it!