Strange noise on cold start up goes when driving

[blake1312]

I have a 2005 1.8t auto, Have a strange noise that I've noticed recently on a cold start up, as soon as I pull away in the car or after a minute or so it will go, it sounds like it's coming from the air box area and kind of sounds like a loud fan. Will try video it tomorrow just didn't know if this was a common fault or anyone had similar as seen a few mention the secondary air causing a problem?

[STAGMAN]

If it sounds like a blowing exhaust, I think it's the secondary air pump. My daughter's A3 1.8T has been doing it for years.

[blake1312]

Are they hard to fit couldn't find any guides online, recorded the sound but having trouble uploading but will keep trying