I have a 1984 Cadillac Eldorado the heat blows through the floor vent and dashboard vent I cannot get the heat to blow through the defroster vent can anyone help me

Ricardo Loranca

• 552 Answers
• Posted on Dec 05, 2008

SOURCE: heat only blows out of dash vents, will not blow out of defroster

vvacum leak. in back of your temp control unit there is a series of vaum lines attached together they might even be in different colors these lines go to the vent and they open and close them when you slide the lever over this piece needs to be replaced

SOURCE: heat not blowing 92 cadillac deville

check you fan, or door controls under dash,
leroy

SOURCE: 1999 cadillac Deville cold air blowing out passenger side vents

Sounds like a Blend door issue, but could be the controller switch, Test ALL modes of operation to see what works and what does not. That should narrow it down a bit. The Blend doors are flap/ doors that regulate air flow, newer vehicles are plastic - electric assemblies ...prone to failure. Any clicking or thumping noises during switching modes and on-off suggest a bad Blend door. Hope that helps...good luck

SOURCE: 1995 cadillac deville 4.9 eng no heat

The heater in your car depends upon a flow of hot coolant going through the heater core in order to get hot air into the car. If the heater core is partially plugged, it will restrict the flow. If you have a head gasket that is putting exhaust into the cooling system, it will eventually get into the heater core. When this happens there is no coolant in the heater core to make the air warm. If the water pump vanes have corroded away the result will be very poor coolant circulation causing the heater to not blow hot air. If your car is equipped with a heater control valve that is not functioning properly, the coolant flow will be restricted. One or a combination of these factors is likely the culprit in your case.

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SOURCE: Heat wont blow through heater or defroster vents

common problem, check under dash by the gas pedal if control arms are muving went selecting from ac to heat cuz this it is the control for the vents to go from ac to heat and to defrost.