White smoke, misfire, knocking, rough idle after sitting for 3 weeks. Help?

[desert_porsche]

You all were awesome helping me diagnose my bad wheel bearings. Hoping you can give me some advice about a new problem I had this morning.

I have the opposite problem of most Boxster drivers, in that I live in Arizona, so the winter is prime convertible time and I park it in the garage during the summer.

After driving it all winter with no issues at all, I decided about 3 weeks ago it was time to put it away for the summer. Before putting it away, I changed the oil and let the engine run for a while to ensure no leaks. No problems.

This morning I decided it would be cool enough to go ahead and drive it to work. It took a long time to crank before it started. Immediately after starting, extremely rough idle. White smoke for a few seconds. There was a loud knocking-like sound as well as what seemed like misfiring. No CEL. After about 30 seconds of idling, it seemed to recover from whatever the problem was, the idle smoothed out, no knocking sound, no misfiring. Drove it into work without any further issues, no smoke, no weird sounds, full power.

What do you think? Air oil separator?