I have a 2007 1500 work truck and now that its turning cold, I discover my heater is pumping cold air. Seems too soon to be a failed heater core. Has any one seen (and cured ) this problem? Any help is appreciated.
Thanks

 

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Louis
GM Customer Service

 

Thanks for your response : from the window sticker: 2007 Classic Silverado 1500 2WD EXT CAB W/T

 

Please dont shoot me for this stupid question but I have to ask the obvious, hows your fluid level in your radiator?

 

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Does the truck have a manual heating, ventilation and air conditioning system? Could you please pm me with your name and VIN number so I could look into this further? I look forward to hearing from you.

Louis
GM Customer Service

 

Thanks! I PMd the vin

 

Good point but it has fluid. Seems to run rather cool as well 185 ish.

 

i've had this problem and it was simple and easy fix. The two hoses that run off the water pump into the firewall, these are hoses that give you warm air when the coolant runs over the heater core. Obviously one goes in and the other returns. Remove both hoses from water pump or firewall, but be careful you don't break the connections on the firewall because they're just plastic if you remove the hoses from there. The heater core is just vents that get garbage on them like rust chips and stuff, if you take a water hose and shoot water into the return line it will push all the garbage off those vents to give you warm air. Hope this was helpful