VS Aircon Hissing

[BIG_JV]

Hey guys havin a bit of an annoying issue with the VS

after the aircon has been on, when i turn the engine off there is a hissing sound for a few seconds. This also occurs occasionally when slowing down while driving.

I have looked around already on the forum but cant find the exact solution.. Do u rekon it needs a regas (after 15y without one) or is there like a loose hose?

It still blows cold air, but its not VERY cold...

 

[Jonno]

Is it like a vacuum leak sound?

 

[BIG_JV]

It is like pshhhhhhhhhhhhhhhh like air escaping. Happens every time i turn the engine off with the a/c button still pressed. i want to try to work out prob before i take it to a mechanic coz 1/2 of them are crooks and try to rip u off

 

[hako]

I'ts probably just refrigerant expanding in the evaporator (!) after the engine is switched off - this is normal although not always audible...just sometimes. You can duplicate this with a refrigerator - when the frig compressor is running, switch the frig off at the wall then put your ear to the outside of the frig and you will hear the gurgling sound as residual refrigerant expands in the evaporator.

 

[Scrubmonk]

I once had a similar problem...

Ended up it was the vacum connections at the back of the vent selection dial (selects fresh, recycle, demist etc). Pop out the gear selector surround, unscrew the stereo/heater control surrond, unscrew the heater selection dial unit. A little bit of vasoline around the connection and made sure it was on securely, and end of hissing.