Somewhere near the center of the dash, I hear a fairly loud vacuum release upon light acceleration and just when I shut off the ignition. What the heck is that? Under the side panels on each side of the console is the "vacuum bottle" with vacuum lines going in either side. If I pull off one of the lines, the whooshing goes away, so at least I think I know the source. Do I have an over-active release valve somewhere? Everything works ok (i.e., defrost, recirculate, and all those things that are dependant on vacuum valves)and all lines seem intact. Any ideas? Thanks.