Check coolant level
Is the car reaching operating temp
if not replace thermostat
if yes
Check heater core hoses if both are hot ,
if both hoses hot and not enough heat inside suspect blend door actuator
if not one hose hot and the other warm or cold the heater core need to be flushed
Oct 8, 2009 at 8:21 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.