1998 Pontiac Firebird Owner's Manual - Page 151

Ventilation System Ventilation Tips Keep the hood andfront air inlet free of ice, snowor any other obstruction (such leaves). The heater as and defroster will work better, reducing the far chance of fogging theinside of your windows. When you enter a vehicle in cold weather, turn the fan controlknob to the rightfor a few moments before drivingoff. This helps clear the intake ducts of snow and moisture, and reduces the chance of fogging the inside your windows. of Keep the air path under the front seats clear of objects. This helps air to circulate throughout your vehicle. Your vehicle's flow-through ventilation system supplies outsideair into the vehicle whenit is moving. Outside air will also enter the vehicle when the blower fan is running.