My 2000 Impala LS V6 engine 3. 8L wasn't bad at first. Till like 3 weeks later after purchasing it, The heat / ac either one I had on would pop off at the slightest bump in the road and pop back on if I hit a big bump. It still came on so I could tolerate but now about 2 months ago it just died all together. The lights on the unit still works fine but it won't blow out a single air through the vents. Not even low air just nothing, either ac/ heat. Though if I turn the dial to cut it on you can kinda tell that its on because of the difference in the way the car sorta drives. I do not hear a fan moving between changing the speed, it makes no sound at all as if a fan is changing speeds or on. I do for some odd reason hear what sounds like running water, which usually I hear after turning of my car. Upon returning to my car later, my passenger seat floor would be soak, once I even seen the water trickling down to the floor from under the glove department. Also the defrost blows very very little, only enough to defrost a small patch in the middle of the windshield, but isn't enough to drive anywhere in it during cold weather or raining days when windows might fog. That's basically the only bit of air that puts out on the car. I heard from 4 different mechanics i usually deal with that said they think it was the blowing motor, the other said it was the blowing resistor, another said to check some hose or wires under my dash board and the last one said, replace the dials and get a whole new ac unit. ( The buttons and dials that used to operate the ac/heat). Neither are licensed mechanics so I would like to here from guys that are. Please help me. . .