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Need Help with ongoing A/C Problem

My 2002 Kia Sedona A/C will cool and then start blowing warm humid air and then back to cool again. So far A/C compressor and reciever/dryer,have been replaced. Evac and Recharge have also been done. Problem is still intermittent and ongoing. I’m wondering if someone out there has had a similar problem which was fixed, or can suggest what else can be done to solve this problem. Thanks

Have you noticed it it only happens when going uphill? If so I’d look for a vacuum problem either letting hot coolant through the heater or a door in the heater/AC malfunctioning. If that is not the case, then I’m confident soneone will have a good answer for you.

Since you say that the air turns humid, we can know that it is not an air door problem. (An air door problem would turn the air warm or hot, but it would stay dry) It is clear that the compressor is cycling off (or otherwise failing to pump the R134).
I would suspect that current to the clutch is being interrupted somehow. It could be that the engine computer is doing this for some reason (like overheating engine, low idle, or WOT) or that the suction pressure is going too low. It could also be that you have a faulty wire, connector, component, or clutch. Was the clutch replaced when the compressor was replaced?

Hi Tardis,
Called the place that did work on car. They said with the new compressor, the clutch is included in it. Also compressor switch on top of the reciever/dryer was replaced. They say maybe something in the car computer is faulty sending bad signals to the clutch. When warm air is coming out of the vents sometimes you have enough time to pull over open the hood and see the clutch wheel stop and start,then stop and start again. Thanks for your reply, and any more information you can add would be great.