My a/c is blowing cold, but now some blows out the defroster on top of the dash and some blows out the vents. This is when the setting is set at just the vents. It has to be a vacum issue, because when I start the car up all the air will blow out the top and then once the car runs for a few min's it will start to blow out the vents some, but still some out the top. If i drive the car down the road, under acclecration it will blow more out the top. Any insight will be thankful. Thanks for your help. If the dealership says they cant fix it, I am going to freak and put nitrous and o/r exhaust on the car. Thanks for you all help.