just make sure if it has a y off somewhere.. cap it if you can... ive seen those come off, and when the fluid cools it sucks air in as the fluid contracts... it can get some dirt and crap in there....

it may seem stupid bubt believe me it can happen...

helll have you ever see the underside of a car with a small leak?? how much dirt and crp collects?

imagine how much dirt taht vent keeps out

 

Plus if it does puke some fluid out someday you don't want it to be dripping on top of the exhaust.