Skip the auto shop - Our mechanics make house calls

Q: Car heater blowing cold air.

asked by on

The car heater is blowing cold air.

A: There are a few different reasons why your ...

There are a few different reasons why your heater could be blowing cold air. First, there may be a problem with your Heater controls. Inside your dashboard there are a series of doors that direct airflow. If one of these doors isn't operating correctly it is possible that only cold air will come out of the vents. The next possibility is that your heater core is blocked or restricted. The heater core is pretty much a small radiator inside your dash that the fan blows air through to get hot air for the interior of your car. Sediment can build up in your cooling system over and clog the small passages inside your heater core. When this happens the coolant can't flow through the heater core and warm the air in the cabin. Sometimes the heater core can be flushed out, but it is also possible that it may need to be replaced if the blockages cannot be removed. The last possibility is that your engine is low on coolant. If coolant has leaked out and there is now air in your cooling system the air cannot transmit heat into the heater core. I would recommend you ask for help from a mechanic to check your car for these concerns so your heater can get back to normal function.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Car jumped and will not start now

If your vehicle is no longer starting, especially after you had to jump it, I would check the battery. It may no longer be holding a charge as it should, and thus is no longer able to start the vehicle...

Q: I'm looking for a quote to replace the timing chain on a S4 4.2L

Hi there, thanks for writing in. He was correct in saying that the chains are on the back of the motor. The engine and transmission must be removed completely, then separated form one another on a workbench, where the chains...

Q: My cooling fan stays on high when car is off can you tell me where the fuse is I can not find it anywhere

Hi there. It is common for the fan to stay on for a short period of time if the coolant is low or if the engine is running too hot. If the fans continues to stay on until the battery...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...