Truck just out of 10 yr storage...I have changed thermostat,blew out interior vents,checked mechanical linkages to controls.flushed heater core.I'm at my wit's end
My truck has 125000miles.
My truck has a manual transmission.been advised to explore vaccum system
This may be related to a faulty blower motor or blower motor relay. The blower motor is a unit inside your vent system that blows warm air from the heater core to the vents when the heater is on or cool air from the air conditioning system when the A/C is on. There is a blower motor relay that supplies power to this motor when you turn the switch to "on" that can sometimes fail. When this happens, you may notice that you will not feel anything blowing out of the vents at all. There is also a blower motor resistor that controls the various speeds and functions of the blower motor once it is turned on. I would recommend having an expert from YourMechanic come to your location to diagnose your blower motor and vent system.
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