AC - Hissing from dash when turned off
#1
On The Tree
Thread Starter
Join Date: Jan 2010
Location: Branford CT
Posts: 159
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
This problem started yesterday. When I have the AC on everything appears to be working normal. The air is cold and when the levels on the dials are changed the amount of air coming out of the vents also change. But when the main AC switched is turned off, I get a hissing sound like air being released from a tire for around 3 seconds. It starts off loud and then slowly disapates. This is the *** that has the ac and max ac selection and only does it for this ***. My v6 camaro does the samething ever since i bought it used and have no idea what it is. Could it be the *** itself or the vaccuum controller? This is such an annoying sound. Any help would be appreciated.
#2
9 Second Club
iTrader: (21)
Join Date: Mar 2008
Location: League City, Texas
Posts: 616
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
This problem started yesterday. When I have the AC on everything appears to be working normal. The air is cold and when the levels on the dials are changed the amount of air coming out of the vents also change. But when the main AC switched is turned off, I get a hissing sound like air being released from a tire for around 3 seconds. It starts off loud and then slowly disapates. This is the *** that has the ac and max ac selection and only does it for this ***. My v6 camaro does the samething ever since i bought it used and have no idea what it is. Could it be the *** itself or the vaccuum controller? This is such an annoying sound. Any help would be appreciated.
#3
On The Tree
Thread Starter
Join Date: Jan 2010
Location: Branford CT
Posts: 159
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
That would suck if i have to get it replaced because i got a new ac compressor last september when i bought the car. The used car dealer that i bought it from was saposed to fix the ac in the contract of the sale. Instead he just recharged it and two weeks later i heard a metal on metal grinding noise. I brought it to another shop and they said the bearing in the compressor were not lubricated and where spining metal on metal. You could see the metal flakes coming out of the compressor. Because i was going back to college and they installed a remanufactured compressor instead of a new one because they were not bale to get a new one in before I left. The ac has always been ice cold and did not have that hissing sound until yesterday which was 10 months after i got a new compressor. Has anyone brought their car the an AC shop and been told where this noise is comign from?
#5
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
This problem started yesterday. When I have the AC on everything appears to be working normal. The air is cold and when the levels on the dials are changed the amount of air coming out of the vents also change. But when the main AC switched is turned off, I get a hissing sound like air being released from a tire for around 3 seconds. It starts off loud and then slowly disapates. This is the *** that has the ac and max ac selection and only does it for this ***. My v6 camaro does the samething ever since i bought it used and have no idea what it is. Could it be the *** itself or the vaccuum controller? This is such an annoying sound. Any help would be appreciated.
#7
On The Tree
Thread Starter
Join Date: Jan 2010
Location: Branford CT
Posts: 159
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Some one please correct me if I am wrong but I dont believe that it is sapossed to happen. My 95 camaro has the same problem and the AC does not work. I tried recharging it and it last for a couple days and then nothing. I am concerned that the same thing is going to happen to my 99 LS1. Has anyone else experience this when the AC is turned off and considers this normal?
Trending Topics
#9
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I have a 99z. I've owned it since 2002. Mine has always made a hissing sound when you shut off the a/c. Still works great. Never bothers me a bit. As long as it still blows cold air and there are no other problems you should be o.k. Unless the sound really bothers you that much I'd leave it alone.
My 2 cents.
My 2 cents.
#14
Launching!
Join Date: Jan 2007
Location: Mooresville,NC
Posts: 233
Likes: 0
Received 0 Likes
on
0 Posts
![](https://ls1tech.com/forums/images/ranks/ls1tech10year.png)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
My 1995 Z did this too and worked fine for almost 4 years. I have to get it checked for leaks and recharged again since the o-ring from the condenser to the aluminum line failed and leaked out all the refridgerant.
#15
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
yeah, typically you can hear it on chevy trucks really well when you turn the truck off it goes HISSSSSS
thats just pressure equalizing from high to low through the oriface tube. usually normal. I'm not real familure with the F-body hvac systems though.
thats just pressure equalizing from high to low through the oriface tube. usually normal. I'm not real familure with the F-body hvac systems though.