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Vibration at idle when AC turned on

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YOUR RESEARCHVibration at idle when AC turned on

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POST 1 / ORIGINAL POSTEROriginal post

As the title states, new-to-me 2000 996 (OEM engine replacement done in 2017, 36K on it now) was delivered with the AC turned off. No weird noises, no vibrations nothing. This is TX, so I turned the AC on within about 60 seconds of sitting in the car, and immediately noticed a slight vibration throughout the interior of the car. No panels rattling or anything, just a slight vibration I could feel in the seats. I don't THINK it increases with turning the AC fan speed up either. Any ideas what the likely cause of this would be? I searched it briefly and in threads across various forums, the responses ranged from motor mounts to the AC condenser.

POST 2Original post

Quotes source post: 19724964

Could you be hearing/feeling the high speed A/C condenser fans up front behind the radiators...? As soon as you turn on AC, the Fans will go to high speed quickly when its hot out at idle, and its very noticeable. Mostly audible, but suppose you could be somewhat 'feeling' it also..? jmo

POST 3Original post

Quotes source post: 19724964

You are right to question that vibration. As allcool said, the fans turn on. And my compressor makes a small amount of noise, but there should not be any vibration. Separately, take a picture of the rear of your car which is eye level to the tailpipes and post it here. We may be able to tell you if you have a motor mount issue.

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