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Hi, I have a 2007 Kia sportage. The ac runs cold then hot like a post from 5/21/2010. you said it was probably the thermistor that was going bad, but if not that a connection in the under hood fusebox. My mechanic said he tested the thermistor with scan tool and then found a loose connection inside the actual fuse box but it could not be tightened the little metal piece was broken, so I bought a new one fuse box and fuses relays were in it. He installed and ac still is blowing cold for a minute and then hot (outside air) could he have missed the scan somehow? He is not a kia mechanic. Do you know how much thermistor fix may cost. what else could it be? Thank you!
My name is XXXXX XXXXX I am a professional here at Just Answer. I noticed that your question was not getting a response and thought I would ask to see if you still need help with this.The first thing that should be done is to check and make sure the vehicle isn't low on freon,if low on freon this indicates the ac system has a leak and is allowing freon to escape.This can cause the ac temperature to go from cold like it should be to warm or hot and back like described here.This would need to be checked with an ac machine to see if it is low,if it is then the leak needs located and corrected and the freon filled to the proper level for the vehicle.If the ac is over charged it can also cause this as well.It may also be a fault with the evaporator temp sensor as this sensor will detect when the evaporator is starting to freeze and cause the ac to shut down like this and the cold to warm air issue.If the sensor thinks the evaporator is freezing up off and on then most likely it is at fault needing replaced.I would start with getting the freon checked to see if it is low or even over charged.If these are o.k. let me know so we can continue.I hope this has helped in some way here.If you need anything else don't hesitate to ask thats what I am here for.If you are not satisfied with my help here let me know before rating my help.Thanks Pete
Hi, Thank you so much for answering. My mechanic checked the Freon and its good. So I think it muse be the sensor. I am taking it back tomorrow and will see what he can do. Thanks again!