Hissing sound after engine is shut off

[Harley McIntyre]

2006 eb v8 ex. Usually after a good drive when I shut my engine off it makes a hissing sound almost like something depressurizing, I listened to it with the hood popped and it sounds like it's coming from the ac area on the passenger side, I've noticed that there will be random leaks, there's sometimes one under the engine, sometimes it's under the transmission, and sometimes it's right under the resonator. I have checked the coolant multiple times and the oil neither of them drop at all. The fluid that comes out seemes to be water, no smell, color, or lubrication properties. I'm worried I have a leak somewhere but I don't know what is leaking and why it keeps changing the places it leaks. The only thing I could think of would be my ac system. Does anyone know what this may be? It only seems to leak when the engine is running.. any help would be greatly appreciated.

 

[974X4BLACKSPORT]

The a/c system will continue to "evaporate" until the pressure in the system equalizes once the system (car) is shut off, this could be the sound your hear. Pure water from the evaporator drain is normal and necessary, make sure the drain tube is clear of debris and unobstructed.

 

[Floridaexplorer43]

Google engine hissing after turning off, could be overheating.

 

[MNgopher]

The hissing sound is likely from your A/C system and is generally normal. The puddles are likely condensation from the A/C, and the locations you are identifying near the engine and transmission sound normal as well. No idea on the resonator other than if when starting cold, you may have condensation draining out of the exhaust.

The puddles are normal when it has been humid. If its anything like its been here for the last week, you leave puddles of condensation everywhere...

 

[Harley McIntyre]

Yeah I'm in Wisconsin so it's been around 100% humidity for a few weeks. Still pretty humid today. Thanks though. I guess I am a little paranoid. I know these suvs with the v8s are reliable but I'm a broke teenager so I am always worried about something going wrong haha

 

[donalds]

Why not run it with the a.c. off then shut it down and see if it hissing

Just shut the a.c. off a mile before you get home