You need to change your thermostat in the car.
faulty control valve on heater or air in the lines
Low on coolant. Bad thermostat. plugged heater core. Temp blend door malfunction.
Have you checked your thermostat?
if car is blowing cold air, you need to check the thermostat,the heater core, and the heat control. the coolant will not blow cold air unless there is no coolant at all in engine,then you have bigger problem anyway
I assume your car heater is blowing cold air, when the heater is on. It seems that, you have air on your coolant. that air pockets blocks the cooland to travel through your heater. it may be a sign of a bigger problem such as blown head gasket in the old cars, such acura legend
Low on coolant. Stuck open thermostat. Plugged heater core. Temp blend door inop.
needs heater core replaced wost likely be hind the glove box
most likely thermostat stuck less than $ 15 part
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.
Check for a thermostat that is stuck open. Also can be a clogged heater core, or defective heater temperture control valve.
it is your heater core most likey