QuestionI have a 2001 Tiburon. The A/C will start out working fine, then will gradually
begin blowing out warmer and warmer air until it is hot air. The fan works fine
and consistently. Freon has been checked, condenser has been cleaned. There
seems to be no pattern for when this occurs, except it is worse on very hot days.
AnswerTerry,
It sounds as though your blend door is opening up on you. The blend door is what separates the heat from your heater core and the cool from your evaporator. It opens and closes dependant upon what you have the control panel set for.
It is controlled by vaccuum lines on many vehicles. The Tiburon, I am unsure of. It could be that you have a pinhole leak in a vaccuum line that is not allowing it to remain closed. Dependant upon how mechanically inclind you are, AutoZone usually is able to print out most vaccuum and electrical schematics. Or if you can round one up from another source, I recommend taking each line that is controllong the blend door itself and testing it. (There will be many lines in there each controlling different panels for vent, defrost, floor, etc.) If no results there, check the vaccuum control manifold for a leak.
Now if yours is controlled by electric, it gets much more in depth, the control head, the actuators, and logic, so I recommend you take it to a reputable shop or even, dare I say it, the dealer *shiver* for troubleshooting.
This is all under the assumption that you had the pressures checked by an actual A/C tech and he blessed off on them, because that is generally the first thing that comes to mind, but since you said you had it checked, I wont go into that area.
I hope I was able to help you a little, thanks for the question and good luck.
