Riz

I'm getting this smell on startup when idling for 3-4 minutes. Stinks up my whole garage. Car has about 800 miles, otherwise everything seems to be fine. I drive it once to twice a week. I definitely get it to warm up, but I'm following break in procedures. Anyone else have this smell from car?

Blue S2

Is your air on? Ive had that problem, or dealt with that problem (friends) on a few German cars. It was always the pollen filter. Your car is pretty new, so i couldn't imagine that filter becoming contaminated that fast. The smell would fill the entire cabin. You say its outside the car too though. Has anything crawled up and died in your engine or trunk? We've seen more that a few stories of animals taking shelter in Porsches.
Good luck correcting this quick! That has to be annoying!

Steve Weiner-Rennsport Systems

Riz:

A rotten egg smell comes from catalytic converters that are running with an over-rich mixture.

Thats something that happens when you start the car from cold and will abate as the engine gets warmed up.

Not to worry,.....

Z06

In some types of gas they have sulfur which will cause that smell,
try a different type of gas.

cosmos

I was just going to say that you should try a different gas. It may have to do with your gas station switching to its "Winter Blend".