Puffing Noise After Turning Car Off?

[davidlee0490]

So I've recently realised that my Polo GTI makes a 'puffing' noise after I've switched the engine off.

The sound isn't constant, and happens in pumps,

I'm not 100% sure where it's coming from, but its from under the bonnet, and is usually accompanied by the sound of water / water droplets?

It usually lasts a good minute or two before it stops (the sound gets weaker instead of suddenly disappearing)

Is this normal?

[RUFNIT]

Howdy,

Probably the turbo/supercharger cooling down. Wouldn't surprise me if VW has programmed in a cool down procedure for them.

MR

[DV52]

So I've recently realised that my Polo GTI makes a 'puffing' noise after I've switched the engine off.

The sound isn't constant, and happens in pumps,

I'm not 100% sure where it's coming from, but its from under the bonnet, and is usually accompanied by the sound of water / water droplets?

It usually lasts a good minute or two before it stops (the sound gets weaker instead of suddenly disappearing)

Is this normal?

Yeah mine makes the same noise. As RUFNIT says, it's the elelctric water pump cooling down the turbo charger. Quite normal (start worrying if it doesn't make the noise)

[nomadx38]

Yeah mine makes the same noise. As RUFNIT says, it's the elelctric water pump cooling down the turbo charger. Quite normal (start worrying if it doesn't make the noise)

Your all close but not right. Yes there is a auxiliary water pump to cool the turbo down after switch off. This is a higher pitched eeeeeeeee which is continuous sound for about 1 minute after engine turn off (dripping water can be heard going back into the coolent reservoir) on GTI's and TSI's (only on really hot days) the radiator fan will also say on for the same amount of time.

Now onto the OP. The ssss....ssss....ssss your hearing is the mechatronics on the DSG releasing pressure from all the solenoids. It usually starts off loud as goes quiet after 30 seconds. This was introduced from the 37g7 service campaign as they found that when pressure is held within the system for a long time (couple of months) the soliends can become jammed and fail to move causing a false neutral and it been unable to move out of Park.

[davidlee0490]

Great to know that it's nothing to be concerned about, thanks for sharing your knowledge everyone!

[alexaescht]

Yes there is a auxiliary water pump to cool the turbo down after switch off. This is a higher pitched eeeeeeeee which is continuous sound for about 1 minute after engine turn off (dripping water can be heard going back into the coolent reservoir) on GTI's and TSI's (only on really hot days) the radiator fan will also say on for the same amount of time.

TDI's do the same thing on really hot days, or if you shut the engine off during a DPF regen.

[gavs]

Your all close but not right. Yes there is a auxiliary water pump to cool the turbo down after switch off. This is a higher pitched eeeeeeeee which is continuous sound for about 1 minute after engine turn off (dripping water can be heard going back into the coolent reservoir) on GTI's and TSI's (only on really hot days) the radiator fan will also say on for the same amount of time.

Now onto the OP. The ssss....ssss....ssss your hearing is the mechatronics on the DSG releasing pressure from all the solenoids. It usually starts off loud as goes quiet after 30 seconds. This was introduced from the 37g7 service campaign as they found that when pressure is held within the system for a long time (couple of months) the soliends can become jammed and fail to move causing a false neutral and it been unable to move out of Park.

This yes, when you first hear it it's very disconcerting but yeah, perfectly normal on post 37g7 DSG's.