When I turn on the air conditioner the air only comes out of the defrost vent
not the vents on the dash the way it used to so as a result it does not work
very good. Is there a relay that changes the air flow? Thanks Darwin
Heat-A/C vent controls are vacuum controlled, so you have a cracked vacuum line, or pinched hose in dash. If you're handy take glovebox out, and then start car (have a flashlight handy) to see what's not moving correctly.
If your heater control is digital it may need to be replaced. Air coming out of the defrost and or floor vent is typical of a bad control module.
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