Hissing noise after engine off

[tonymy01]

? The throttle plate isn't a perfect seal closed, so if the engine isn't running, atmospheric pressure will be coming between air filter intake and engine valves. Vacuum is only in there due to the engine sucking air in while running. The crank case will have a little vacuum too from the engine vacuum via PCV, but that would dissipate almost immediately too I would think.

[90tsiwagon]

I have just picked up my 90tsi golf wagon. The salesman told me that when i turn the car off sometimes i will hear a hissing noise. He explained the car is pumping fluid to the turbo to cool it. He also said the hissing would last sometimes up to 60 seconds. Hope this helps
Cheers

[Ryan_R]

Yes we are all familiar with that - it's jut the nature of the hissing suddenly changed from constant to intermittent after the DSG recall which was a little strange

[shaguar]

I have just picked up my 90tsi golf wagon. The salesman told me that when i turn the car off sometimes i will hear a hissing noise. He explained the car is pumping fluid to the turbo to cool it. He also said the hissing would last sometimes up to 60 seconds. Hope this helps
Cheers

Agreed. That's what the technician told me as well but agree with Ryan that its strange it went to intermittent and not constant.

Also the technicians said its a self checking mechanism for the new transmission? (recall)

[xordis]

Add me to the list as well.
118TSI.
I had the recall fix done last Friday, and every time I drive it now it will hiss when I stop (maybe even when it's running?)
Seems consistent, 1 second on, 1 second off. I cannot see any fluids leaking underneath or in the engine bay.
I think it may have replaced the constant sound of the pump running to cool the turbo? Hard to tell as I was used to it.