I have a 2003 Siera pick up truck ans the heater is blowing out cool air and it only comes out the top not the vents what is my problem, I flush the radiator and put fresh anti-freeze and water in it


Asked by Dec 29, 2015 at 08:33 AM

Question type: Maintenance & Repair

2003 GMC Sierra pick-up truck 2500 v8 4×4 heayer
just blows out cool air

3 Answers


I tried flushing the radiator out and puting fresh anti-freeze and water in it


I put a heater control swicth in it and replaced the recister in it


Either needs a thermostat, or the cooling system needs to be purged from air pockets, and or the blend door actuator is not working to allow the blend door to close to the outside air.

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