I just got my Jeep & am a first time owner of a Jeep. When I bought it, the guy I bought it from told me I needed to keep the vent on the hood near the windshield cleaned out or it can leak into the cab if it gets stopped up??? I didn't ask any questions at that time but now realize I should have. Can someone explain what he was talkking about? Also, I;ve seen on Ebay different types of things called vent covers or air scoops that can fit over this.....do I need one?