Adam 
the whoosh you are hearing is the air going into the tank not coming out. This is most likely due to a bad valve for evaporative emissions system. Trace the plastic purple vacuum hose from the intake manifold to the valve. the valve most likely has a hole in it and that is pulling air out of the gas tank you need to replace the valve.   
Bob Donalds 
http:.//www.bostonengine.com