Whining sound on cold starts,comes and goes
 

Ever since the weather has become colder here in California I have noticed that my Boxster at start ups has a whining sound(Iam the only one that notices it,but it annoys me). The sound can be heard for a few minutes at a cold start then turns off,the idle drops a little when that sound goes away. When I drive I cant hear it but at the first stop I come to it seems like the whining comes back for a few seconds and goes away,the idle will rise and drop a little as the sound comes and goes(I think a device may be turning on and off). After the car has ran for about 5 or 10 minutes the sound is no where to be heard. It doesnt change how the cars drives or performs in any way but its one of those annoying things I would like to eliminate if possible. Any input as to whether or not this may be normal would be appreciated.

Sounds like a secondary air pump. I had the exact same thing on my Audi. Not really sure what it does, but was told it's not an emergency to get fixed but I got it fixed within a week of it happening.

Hi,

The Secondary Airpump is an Emissions Device which adds Air to the Combustion Mixture when the Engine is Cold to promote more complete combustion, and thereby fewer Emissions. It is controlled by the DME. This Pump has Bearings and Vanes which can wear out - they will all eventually require replacement.

It won't affect the Car's Performance, but may make the Idle rougher or trigger a CEL (because Emissions go beyond Spec at idle or when Cold). If it's not too noticable, I wouldn't worry about it. It will probably quiet once your Ambient Temps return to Normal. Hope this helps...

Happy Motoring!... Jim'99