Q: What is the high-pitched whistling noise when my a/c is turned on? on 2007 Hyundai Elantra

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The a/c works fine but when it becomes hot outside, the noise gets louder. The max a/c setting on the knob does not work at all either. As you accelerate, the noise gets louder as well.
(3) Answers
It could be your sway bar. If it is snapped it will make a thumping noise when you steer and will make no noise when going straight. It needs to be fixed immediately.
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