I have a 2004 Regal. When I push the button for the defogger the blower works but the air flow is not directed up to the windshield.

I have another problem which may not be related...my air conditioner works intermittently. The blower comes on but I don't always get cold air. Sometimes I let it run for a while and I start getting cold air, sometimes not. One mechanic told me that my freon was low and added some... the problem persisted, and it cost me $80 for nothing.