I just purchased an 06 Carrera S with sport exhaust. I seem to remember on my 05 with the same option, an "on/off button" for the exhaust. Did they make a change and do away with the button on model year 2006?

 

it's the 'SPORT' button in the center console, should be right above the storage bin.

 

If your 2005 didn't have Sport Chrono and PSE was factory installed then a switch (w/ a tail pipe icon) was provided. Now, if your 2006 has Sport Chrono and factory PSE the PSE 'loud' mode is only activated when in the 'Sport Mode'.

I hope this helps some.

 

I have a 06 Carrera S as well with sport chrono. When you press the sport button, it activates the sport exhaust. It's only active above certain a speed or rpm. I can't remember exactly. I had the dealer wire mine with a separate button in the round hole in the ashtray so I have complete control independent of the sport button. It's nice that way. Sounds good when you crank it up and at low speeds . Hope this helps.

 

I forgot to mention it was by using the search on this board that I figured this out. This board is truly a great resource .