Ventilation system blows air into cabin through insturment-level dashboard vents, even when fan is off and vehicle stationary, and even when fan is on but directed to foot only or defroster only. Pontiac dealer service dept and Pontiac national customer service claim this is normal. I have never seen this on any other vehicle. There is no way to shut off the flow from the middle (over the radio) vents. Tehre is a "wheel" to block the flow to the center-left and center-right vents above the radio, but no such control for the center-center vent--it only adjusts up/down. This is causing discomfort but above all can dry eyes out while driving. It makes no sense. Even the service advisor immediately thought it was a defect. He changed his mind when he found the same condition on other 2003 Montana on lot. I submit that this is not normal and may reflect a design and/or manufacturing defect that has safety implications. Please note that reciruclate is designed not to work in all modes either.

- Melville, NY, USA