The center vents close when I accelerate and open when I let off the pedal. I get more defrost when I accelerate as well. I know that there may be some vaccum elements that are bad, but when I was in Miami (not anymore) my idny told me that the block was bad. He said no lines would hold a vacuum. So...that is how I came to a conclusion that I needed a new block.


98 CLK 320