I've noticed a high pitched whine/whir sound coming from under the hood after I've shut off the car. It continues for a while after I shut the car off, but if I twist the radiator cap and release the coolant pressure (not sure what possessed me to try this), it stops. Any ideas on what it might be?

 

Sounds like the coolant circulating to cool down the turbocharger. It stops automatically after about 5 minutes.

 

Unless it's really high pitched it's normal, I believe it's an electric pump cooling off your turbo. If it's really high pitched and loud it might have a problem.

 

I would not recommend releasing the pressure from the radiator after you have been driving for a while. And yes, it is the after run pump to cool the engine and turbo after you shut the car off.

 

sweet, glad to know it's normal. Scottab - I don't regularly do that I was just trying to figure out what was causing the noise (and I took all the precautions to make sure I wouldn't burn myself )

Thanks for the quick reply guys!

 

Good to know! I thought I would throw that out there as I have watched people just whip that radiator cap right off on a hot engine.

 

Hi
Just seen message regarding noise after shut off - happened to me too. Never heard the fan after switching off my car then it started doing it one day. A few days later I was sitting in slow moving traffic and my car overheated. Had to turn off, wait for car to cool then drive again. Turns out the thermostat had blown. Explained the fan having to work overtime to cool the engine after switch off.
All covered under motorplan - so worth checking out too.

 

Everyone beat me to the punch!!!