yesterday for the first time ever i opened the gas cap on the trail i had about 1/4 tank and when i removed the cap i got a quick pssssss of air going in of course because the tank does cause a vaccum on a fuel injected atv. the dealer said this 100 percent normal and theres no blockage in the vent and when there is less fuel in that tank you will have air rush in because its a sealed unit does anyone elses unit does it not that i dont believe the 3 dealers i called lol