When I cold start my TT (sitting for about 3-4 hours) my car has a loud whining noise. As the idle drops, within about three minutes tops, the noise quiets down and then goes away altogether. The one time I decided to drive it while it was making this noise, there seems to be little to no boost. After it goes away, the car seems to boost fine. I have no idea about the vehicle's history - I just bought it last week. It currently has just over 80K miles.

I realize this would be better if I had a soundclip (I should be able to get one up by this weekend), but wondered if anyone had experienced this before.

 

Its normal.

 

Seriously? I used to have a 2000 180HP Quattro and it never did that.

 

Yes, its the SAI (secondary air injection) pump making the noise to heat up the cat.

 

Wow... Sorry for the dumb question then, but thanks for info (and putting my mind at ease).

 

Does it cause any damage or s it jus an embarrasing noise?
Is it expensiveto fix...ball ark?

 

anyboby got a ball park cost?

 

yes about $900 - $1100 i think is what we paid, it sucks

yes it is the secondary air pump.

 

managed to get it done under the used car warranty, they fitted a brand new unit (Garage told me it was £350 plus £60 fitting).
Very happy

Quiet as a mouse now

 

I recently got my car back from the shop after extensive work being done to the transmission and clutch. (1998 A4 2.8L Quattro) And it Just started making this noise. Like STEVEBOOTH had asked, Is it damaging my car? Or is it just embarressing to listen to?
I often wait until my co-workers have left before starting my car due to the ugly @$$ noise it makes!

Thank you for your help... :-D