...to change which vents the AC blows out of?

I know you can direct it at the windshield by pushing the defog, but is there a way to make the air come out at the foot well only, or dash only etc.....most cars have a lever/button that lets you select where the air comes out of.

I am pretty sure your car is like mine and air delivery is determined by the ACM (programmer). A/C from the vents and heat from the floor.

yeah.....its kinda wierd that you can't select it manually.

I sometimes want cold air at my feet.....but I guess Caddy never thought that was needed.

you guys are lucky ...i cant even get recirulate ....stupid communist Airconditioning ....

got stallin inside my dash decideing whats confortable ...bastard

you guys are lucky ...i cant even get recirulate ....stupid communist Airconditioning ....

got stallin inside my dash decideing whats confortable ...bastard

Really? You don't have that auto/econ button? (I am guessing this is what it does)

yeah, thats pretty weak......twilight sentinel/auto-closing trunk but no vent selector!

I can tell that it sometimes switches between dash and windshield vents, how does it 'know' to change vents?

Defrost is the default position. If yours is switching to defrost on it's own I would suspect a vacuum leak somewhere. Vacuum will get low at higher throttle settings. Is that when you notice the switch?

Not sure.....I think its happened to me at low speeds too (dunno about throttle position).
I bet its a real hassle finding/fixing vacuum leak right?

It can be. Depends on where the leak is. A stethescope is sort of like a geiger counter when looking for a vacuum leak. Start at the firewall on the passenger side and follow the supply line back to the reservoir. Inspect the lines and the reservoir for cracks. If all that is good then comes the harder part, under the dash.