I think there is a thread about this somewhere else. I'm not sure EXACTLY (so don't break my balls here guys) why the engines do this but the P5 has an Ultra Low emissions engine and this revving on start up has something to do with bringing the engine to operating temps faster so that the emissions systems work more efficiently. It's NOT a problem it's normal. The car will rev to maybe 1500 or so for a minute or two and then settle back down to normal idle speed. Do a search and maybe you can find an answer thats more technically correct.

I did search... all I am asking is for a few people to check whether their P5s rev past 2K RPM when cold started. You and others have mentioned 1500 RPM, and I think there is a significant difference in 2000 RPM.