Question about 1994 GMC Yukon

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Heater does not blow hot air

I changed my heater core, all the settings work, but the digital cold to hot bar on the bottom of the heater display blinks with all the arow lit up but the air is always cool. I checked the fuses but they are fine. help please

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  • scoulombe Mar 16, 2009

    The blend door actuator may be bad. Located behind glove box on top of the box left.

    Does anyone know if the 94 Yukon heat system controls the cooling fluid with a valve at al or not?

  • Mike Butler
    Mike Butler May 11, 2010

    You bled system properly with rad cap off & heater on after changing core?



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You might need to change the thermostat.. when the thermostat isn't working correctly it prevents the hot engine coolant to circulate and give you heat.

Posted on Apr 28, 2009


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