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Anonymous Posted on Apr 04, 2009

Chevy 1500 Heater problem

I have a Chevy 1500 Z71 pickup and the heater does not put out hot air unless I keep the RPM above 2000. Once it gets below That the heat begins to go cold as if the hot water flow has stopped. Can anyone help?

  • 2 more comments 
  • Anonymous Apr 04, 2009

    no it does not overheat

  • Anonymous May 11, 2010

    Do you have the proper coolant level in the reservoir?

  • Anonymous May 11, 2010

    Do'es the vehicle overheat when it idle's?

  • Anonymous Mar 17, 2014

    heat hand goes up slowly above hot then drops below cold then stays on cold

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  • Posted on Apr 05, 2009
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It sound's like a problem with the water pump, thermostat, or drive-belt, drive-belt tensioner and pulley, check the tension on the drive-belt, if it has good tension check and or replace the thermostat, if your still having cold air coming out at low rpm's it could be a bad water pump. you can check the water pump by looking to see if there's coolant leaking from the weap hole, or listen for a squealing noise from the water pump when the vehicle is running, there's also a possibility of air in your cooling system which usually occur's when you have the coolant system opened up for repair's, if there is air in the system it could keep the coolant from flowing properly, only way to get it out is to bleed it out using the bleeder valve, im assuming the coolant level is at the proper level,
I hope this was helpful. Good luck.

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