I have a 2001 Jeep Grand Cherokee and have a problem with my air vents. Anytime I use my air, a/c or heat, it only blows out of the defrosting vent and not the floor or dash vents. The problem first started only when I would press the gas, now it happens all the time. Not sure what the issue is. Do I need to take apart my whole dash? Please Help!
sounds like you have a vacuum problem. The first thing I would check is for vacuum to be getting to the vac line that runs inside for the HVAC. Chances are it will enter through the firewall where the A/C lines go through or where the heater hoses are. You probably have a rotten vac hose goping to the vac storage ball.