Skip the auto shop - Our mechanics make house calls

Q: Heater stops working during idling

asked by on

I have some issues with the heater in my truck. I replaced the antifreeze reservoir anlong with the water pump. Also, I had the radiator flushed. However, the heater stops blowing warm air while the truck is at idle. There are no leaks. The heater would start working if the idling speed is increased. What is causing this?

Hello. I recommend checking the operation of the thermostat to ensure it opens and closes at the proper temperature. You also could have some air in your cooling system causing the heating system to blow cold at inappropriate times. To remove the air from the cooling system a technician must bleed the cooling system.

Anytime there’s a repair done on the cooling system and coolant is lost you must bleed the coolant system. If the coolant system is not bleed it may cause the vehicle to overheat from air trapped in the system or incorrect temperature from the vents.

If you need some assistance with this, consider getting some help from a certified mechanic who can diagnose the issue with your A/C first hand and address any other problems that may arise.

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・Fair and transparent pricing

Get a quote

What others are asking

Q: Van is choking and stalling

If fuel is not getting to the carburetor, then you have one of a few different problems. The most common would be the fuel filter being clogged. Depending on your engine you may have one or more fuel filters both...

Q: Air conditioning not working

The most common cause is low or no refrigerant. The system would need to be checked for leaks before recharging. Leaks can occur anywhere. If this is not the case, there are many other problems that can cause the AC...

Q: Service Engine Soon Light came on yesterday.

While the oxygen sensor may be the cause of the service engine soon light coming on, it's best to have a certified technician correctly diagnose why the service engine light is on. When the service engine soon - or check...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...