Sounds like a stuck thermostat.
My heater doesn't go cold. But to answer your question, check the engine coolant level in the radiator. Be sure that the engine is cold before removing the radiator cap. --Ken
A car heater taps off engine heat. If you aren't driving, then the engine is cold and there's no heat for the car heater to use.
Feel the temperature of the heater pipes in the engine bay, where they pass through the front bulkhead. If they are both hot then the fault is most likely the air regulator flap stuck. Look here http://tinyurl.com/67pl3d for help.
A common cause is the thermostat being stuck in an open position.
The #1 cause of cold air from the heater when the car is stopped, or the engine is idling, low engine coolant levels.
Interior heat uses the engine heat. If the engine is still cold, the heater will blow cold. If the engine is warm and the heater is blowing cold, you have a problem with the heater. Check the water in the radiator and see if it is rusty. If it is rusty, change your coolant, thermostat, and hoses. Look at the heater hoses when someone steps down on the gas pedal. If a hose collapses, replace your heater hoses. Otherwise take it to a mechanic.
An engine block heater for a 2004 Hyundai Tiburon is a part of the engine that helps keep the engine warm when it is very cold outside. It has a plug that needs to be plugged into an electric outlet when the car has to sit in the cold weather.
Check to insure that the engine coolant is full and the thermostat is not stuck. Without the heated fluid from the engine the heater will always blow cold air.
if youre trying to turn the heater on and cold air comes out, then its most likely the heater core
Is an electrical device used to heat coolant of a vehicle at extreme cold condition for easy startup.
AnswerBad thermostat, clogged heater core, or a defective heater control switch. If an engine has not been running long it will not have warmed up, the warmth from a car heater usually comes from the engine.
it's old and you need to change it.