Noise after shutdown

[Omega]

Hi folks,

We've got a 2007 Jetta FSI and when I turn off the ignition and get out of the car, I notice a whining noise coming from the engine bay; it's a high-pitched noise, like an electric motor and goes for about 10 seconds.

It is similar to the noise I hear when I first get into the car which I have learned from this forum is the fuel pump priming itself ready for action. But the noise I hear after shutdown is different - so what is it?

Any feedback appreciated - thanks.

[wokwn]

Turbo cooling pump.

[Omega]

Thanks but it's not a turbo engine. It sounds similar to the fuel pump priming but a little louder and only noticeable if I park in a quiet area like in my garage. The sound is a bit like, if you can imagine, a robot (transformers!) moving it's arm or leg, or opening/closing a cargo door or canopy on a military aircraft.

[satz]

i think it's the high pressure fuel pump(for the direct injection) depressurising.

My mazda CX7 used to make a similar noise, as does my 08 GTI


cheers

S

[Greg Roles]

In the TDI it makes a high pitched whine for about 20 seconds, and this is the shutdown flap remaining closed blocking air from entering the inlet. Perhaps the FSI has a similar shutdown operation included in the throttle assembly?

[macdoc]

Its the electronic throttle body unit, it performs a post self test.

[Omega]

That makes sense. Thanks for clearing it up.