1999 Buick Riviera Owner's Manual - Page 150

yellowblue Adjust the direction of airflow by moving the louvered air outlets. You can also adjust the direction of the airflow to the rear seating area. Ventilation Tips D Keep the hood and front air inlet free of ice, snow or any other obstruction such as leaves. The heater and defroster will work better, reducing the chance of fogging your windows. objects. This helps air to circulate throughout your vehicle. D Keep the air path under the front seats clear of 3-8