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Q: Heater stops working during idling

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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.

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