The AC on a 1998 Dodge Ram 1998 will only be blowing out the defrost vent if the air handler is not set properly. This can result from a piece of debris getting stuck or a faulty flap.
does fan door motorized or on a vaccuum line when you switch from AC to defrost?
That means either you have air in your heater core or your heater core is being bypassed
If central air conditioner turns on but is not blowing through the vents, check the filter. If it is dirty, change it. Change the thermostat into cool, this will defrost the air conditioner.
When there is a problem in the vent system it defaults to defrost setting. Check the doors & vac supply
You have a vacuum leak causing your vents to switch from dash to defrost.
If you can Not change the location of the air flow to the different outlets (defrost, dash, floor, etc) That sounds like a mode door problem or a mode door control knob.
If you feel no air blowing at all (when you are not moving) then your fan is not blowing. If it is blowing air, and it is cold, when the heater is on, then most probably your heater core is leaking, or is clogged. These are easily replaceable and go bad all the time in older cars.
crack a window open to let the moisture of your breathing get out and set your air control to exterior air
Check the vaccuum hoses going to your manifold- The one that controls air flow direction to your AC is probably split Astroman
It have battery
ihave a 1986 chevette that when i turn defrost on it blows out heat and when i put heater on it blows out only cold air? ihave a 1986 chevette that when i turn defrost on it blows out heat and when i put heater on it blows out only cold air?