Question about Hyundai Motor 2004 Sonata

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04 Hyundia Sonata LX, engine performance drains with AC running

I have an 04 Sonata LX that runs great with the AC on when outside temperatures are below 80 degrees, but when the temps. get over 80 degrees the problems start. Yesterday it was 87 degrees in Ohio and the car ran great with AC on for about ten minutes, then the dragging feeling started. The engine felt like I was pulling a trailer and the transmission felt like it was trying to shift to maintain the speed. It is really noticeable when you go up a slight grade. My local garage can not find anything wrong with the compressor, but they were checking the car in the morning when it was still cool outside. I am going to try and take it back to the garage when it is hot and acting up again to see if they can catch it in the act, problem is it is getting costly with no results as of yet. Is there some type of temp. sensor that would be causing this action to happen? Thanks for any help, Jeff

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Dear friend-you are correct when you say it can be a tempreture switch that might be at fault.your air con take a lot of torque away from your engine when kicking in so you need something to compensate and restore the torque.a sensor is added into the system to do exacly that and works of a signal coming from the temp switch.that unit is normally mounted on the fire wall.

Posted on Jul 20, 2009


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Posted on Jan 02, 2017


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