Hey,
I've had the same problem now for a while.
I have a 2000. boxster.
I noticed though if I turn on the A/C, the idle fluctuations are minimized...a lot.
I've only noticed it after the car warms up.
During the winter months in Atlanta, I didn't appear to have had the problem.
Also, it doesn't happen every day and I get no dash lights stating there is anything wrong.
I hope this info is useful. If it continues I guess I'll seek the dealer.
Regards,
Will
