hubris140

Hi folks,

Yesterday after I switched off the car, I could very clearly hear short hissing/gasping noises every 5-10 secs in quick succession. The noises continued for about 15 mins or so after the car was turned off. To me, it sounds like some kind of vaccum pump turning on/off every few secs or so. I took a short video here: Video

Kinda paranoid thinking if this is some kind of engine system leaking/losing pressure when it shouldn't? Is this a serious issue? Has someone encountered this before?

(Car seems fine on startup, no warnings, pulls hard as usual, etc. Only mod is a Borla X pipe)

Demnos

unfortunately I dont have access to the video right now but 99 times out of 100 hissing is the ac dripping water on the hot exhaust

hubris140

This sounds more mechanical though like some pump actuator working (if that helps). I've heard the A/C condensation on exhaust sound in my old C6Z and this sounds different (even though its technically 'hissing'). Not sure how best to explain.

Sixgun95

Its rhe AC condensation dripping on the exhaust. Its normal.

orca1946

That's good to know when it happens to me. Thanx.

LuisZ51

Mine hisses, pops, chugs and gurgles for a few min after I shut it off. Pretty sure it's all normal.

ShadowGray19

Happened all the time with my 2015. Have not heard it at all with the 2019

Demnos

Finally was able to see it. That sounds like something slowly rotating and grinding on something more than the exhaust hiss

Skid Row Joe

Water condensation from your AC (climate control) dripping on some portion of your exhaust assembly.

owc6

This has been reported several times since the car's introduction; It's been said that it is the AC Compressor Shaft/Clutch.

https://www.corvetteforum.com/forums...on-is-off.html

2019GSTX

Is ur key in ur pocket?
go put ur key in the house and then see if u hear the noise. I noticed it yesterday when I was crawling around the car.
Something is activating when the key fob is close to and then away from the car

gmarcucio

It might also be the AC system high and low side pressure equalizing after the system is shut down.

owc6

Nothing is activating the car by being close or in proximity to it.

The fob and car only talk when a button on the fob or car is pressed. Being near makes no difference, they aren't questing for each other. That would take a lot of battery on both the fob and the car, and was annoying as hell. The last Corvette to do this was either '98 or'99 ( I can never remember which).

Maxie2U

I had that same “chirping” sound back in April of last year. I brought it the dealer who spoke with a GM specialist.

Problem statement

• Mechanical "chirping" noise coming from a/c compressor after shutting off engine.
  • 10 minutes after shutting off the car what could best described as a chirping sound coming from the front of the engine compartment. The sound lasts about a second or so. It repeated every couple of minutes (in some cases it repeats more often) for about 1/2 hour after shutdown.
    • The noise is due to a faulty A/C compressor shutoff valve that momentarily opens and closes making that weird noise under pressure. If it occurs on a regular basis replace the A/c compressor.

In my case, it stopped chirping without having to replace the compressor.