Hi:
Your problem may have to do with the heater core. It could be plugged. Under the hood of the car, and locate the two heater core hoses. They will go to the firewall. With the engine running, at operating temp, and the heater on, feel the hoses. They should both be hot. Keep in mind, one is an inlet, the other is the outlet from the core. If one is hot and one is cold, the coolant isn't flowing through the heater core, therefore no heat.
NOTE: When checking the hoses, they will be hot! THe engine runs around 200 degrees so if you're not careful, you could be burned.
Let me know if this helps.
Joe
Oct 26, 2008 at 2:48 PM