Most likely your heater core has a leak. Your heater core is leaking. It must be replace to correct this problem. Anytime you get an anti-freeze smell, this usually indicates a leak in the system, usually the heater core. Have you noticed if the floor is wet under the area where the heater is located? Look for wet carpet on the floor of the passenger side front. Most 3.8 liter GM engines from the early to late nineties develop an intake manifold leak at some point. This is characterized by an antifreeze odor, rough idling, poor mileage, a lack of heat, and antifreeze appearing in the oil. Simple enough to fix, just replace the intake manifold gasket. Might as well clean the throttle body and change that as well. Repair cost for that job plus a tune-up: $600-700, for just the manifold gasket, you'd most likely stay around $300-400.
You have a blown head gasket. Antifreeze that should be going through a hole in your gasket and then cooling the engine head is going into a cylinder. From there it is going out an exhaust pipe as steam. It is also getting into an oil drain hole and getting into the oil pan. It is inexpensive to get a head gasket fixed compared to the cost of having a blown engine replaced.
The vacuum supply line from the engine is disconnected or broken. When the vacuum supply is cut off the system defaults to the defrost mode.
Through the radiator cap no... But it does allow the antifreeze to come out through the cap if the pressure gets too high.
A gm 3.8 l v6 or 3800 cc engine cannot have antifreeze in exhaust without first getting into the engine. If its getting into the exhaust it may be entering the cumbustion chambers through a damaged cylinder head or head gasket. Also this engine depending on the model year may have issues with the intake manifold gasket, that can cause antifreeze to leak into the engine oil.
My first attempt would be to replace the fuel filter if it is not getting gas second would be the fuel pump also check for spark and compression
Antifreeze will be leaking in the floorboard on the passenger side, there will be a smell of antifreeze through the vents.
If your going through coolant then you have an internal head gasket leak you smell coolant because its getting into cylinder and burning
the antifreeze runs through all your water lines in your car . . . . you put it in your water tank or radiator
you have leak somewhere
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.
The water pump will pump coolant(antifreeze & water) through the engine after the thermostat opens up.