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.
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2007 Hyundai Elantra Question: What is the high-pitched whistling noise when my a/c is turned on?
COULD BE IDLER BEARING GOING BAD AND ONLY MAKES NOSE WHEN UNDER A/C LOAD
Answer #2pushrod May 07, 2013, 07:03Master
Also have the ac compressor belt checked could be loose or defective. Has it's own belt.
Answer #3wenyan May 10, 2013, 04:26Technician
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.http://www.lightdeal.co.uk/