Skip the auto shop - Our mechanics make house calls

Q: My air conditioner works great but the Heat doesn't air blows out warm at first but then cools down after a couple minutes

asked by on

I have barley have any heat. It starts out warm then within couple min it cools down. Air.conditioning works great. I've had the thermostat and sensor replaced and nothing. Any idea why this would b happening?
My car has an automatic transmission.

Hi there. The lack of heat could be, the heater core is restricted. A cooling system flush could return proper flow through the heater core. A faulty heater control valve could also prevent proper flow through the heater core.There is the possibility, the temperature blend door actuator is faulty not fully changing the blend door in the HVAC (heating, ventilation, air conditioning) distribution housing. I recommend having your vehicle’s heater doesn’t work properly be diagnosed and repaired by a certified technician, such as one from YourMechanic.

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!
  1. Home
  2. Questions
  3. My air conditioner works great but the Heat doesn't air blows out warm at first but then cools down after a couple minutes

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: have a ex royal mail ford transit 06 plate and want to get the central locking on front doors back to original format

YourMechanic is based in the United States, so we do not have access to service information on your vehicle. I suggest purchasing a service manual so you can research what components are missing or not working properly. If all the...

Q: Car starts but won't run.

If your engine starts but won't stay running (idling) the problem is most likely a faulty idle air control (IAC) motor. The IAC opens and closes to maintain engine idle, if this component goes out, the engine will keep stalling. A...

Q: Belt noises pulley wobbles

Hey there, thanks for writing in about your 2005 Pontiac GTO. Worn idler pulleys or accessory components along the belt drive system may make noise as a sign the bearings are failing. As far as the brands, stick with OEM...

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...
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...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...