# Random AC Depressurization Question

**URL:** <https://community.cartalk.com/t/random-ac-depressurization-question/85656>\
**Category:** General Discussion\
**Created:** [June 26, 2014, 11:10pm UTC](https://community.cartalk.com/t/random-ac-depressurization-question/85656 "2014-06-26T23:10:50Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Fender1325](https://avatars.discourse-cdn.com/v4/letter/f/96bed5/32.png) [@Fender1325](https://community.cartalk.com/u/Fender1325)\
**Post date:** [June 26, 2014, 11:10pm UTC](https://community.cartalk.com/t/random-ac-depressurization-question/85656/1 "2014-06-26T23:10:50Z")

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Ive always noticed that if Im running the AC, and turn the car off, then move the AC knob to the off position, I hear the internal doors move and the system sortve depressurize and let out a pshhhhh sound. It does it on my 03 f150 and it did it on my 98 mustang. Call it OCD, but out of habit I always make sure its turned off before I leave the car for the evening or where-ever. As if to make sure the system isnt holding some kind of pressure. Im guessing it doesnt make a difference what you do, or does it? One of those funny habits.

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**Author:** ![insightful](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/insightful/32/2732_2.png) [@insightful](https://community.cartalk.com/u/insightful)\
**Post date:** [June 26, 2014, 11:42pm UTC](https://community.cartalk.com/t/random-ac-depressurization-question/85656/2 "2014-06-26T23:42:08Z")

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When the AC compressor shuts off, the refrigerant pressure in the system will equalize no matter what else you do.

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**Author:** ![missileman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/missileman/32/1366_2.png) [@missileman](https://community.cartalk.com/u/missileman)\
**Post date:** [June 27, 2014, 6:17am UTC](https://community.cartalk.com/t/random-ac-depressurization-question/85656/3 "2014-06-27T06:17:46Z")

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I agree. My AC switch stays in the same position basically all summer long.

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**Author:** ![Fender1325](https://avatars.discourse-cdn.com/v4/letter/f/96bed5/32.png) [@Fender1325](https://community.cartalk.com/u/Fender1325)\
**Post date:** [June 27, 2014, 7:13am UTC](https://community.cartalk.com/t/random-ac-depressurization-question/85656/4 "2014-06-27T07:13:02Z")

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Yeah, just a weird habit I guess.