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91 coupe, climate control: Added freon last year, AC worked great. This year first time i turned it on .......fans kick on, AC tube under hood very cold and frosts up. VERY hot air in cabin! No flashing LEDS. Engine wants to "Miss" at idle. I disconnected the neg bat for 30 secs, pulled the cursty and radio fuse, no help. Suspect a switch or sensor.
If it is cycling more off than on or 10 times a minute, that might indicate low Freon. The low side frosting up might be bad sign. It should be ice cold and sweating.
On the other hand if the Freon is good, the blend door may not operating properly. It may be sending heat into the car rather than the A/C air. I would pull the blower motor power module from the top of the evaporator box and look in there with a flashlight. Have someone run the temp control from full cold to full hot (key on) and see if the blend door is moving.