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  1. #1

    Default A/C not blowing hard

    Has anyone had issues with the volume of air coming out the dash vents when the ac is on. my 90 2500's ac is ice cold. when the fan is on high it has normal air flow after a while the airflow decreases. it will not increase untill the truck is turned off then restarted ac on fan on high.although this does not always work. does anyone know how many blend doors and dirverter doors and controlers there are for a truck with electronic hvac controls. my controls are not acuated by cables and i do not have max or recirculate switches just ac on and off. my fan motor is new. thanks for any help.

  2. #2


    Sounds like you got a door not opening all the way. My first sugestion would be to check for worn, broken, r leaking hoses behind your controll pannel beyond that is out of my knowledge. Hope i was helpful, in the meantime ill see what i can dig up let me know if you figure it out

  3. #3


    I've got the same issue going on in my 96. Fan speeds work fine, but volume of air coming out is minimal.

  4. #4


    my chilton book only has the cable/vacuum type controls,not the digital like my truck. its a silverado not sure if just those models have digital control pannel. went to chevy they printed out hvac plenum diagram. looks like one motor controls the mode function(def vents floor) and a motor to control temp(hot,cold) a resistor to control fan speed and the hvac digital control pannel itself. bought a resistor from chevy for around twenty dollars its behind the glovebox on top of plenum pretty easy to get at. hopefully it fixes the problem if not ill replace both control motors they are around eighty dollars each and easy to get at. the temp motor is behind glovebox screwed to plenum and mode motor is near throttle pedal and transmission hump, on plenum. driving the truck a lot this weekend so ill know soon.

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