All 6 cylinders misfire

[dogsivew]

First off, I just bought my first Boxster, 2004 Base 65,000 miles, a week ago and love it. Secondly, I appreciate all the information available on this site as well as Mike Focke's page, they have helped me out greatly.

Yesterday my check engine light came on and has stayed on(not blinking). I went by Autozone and they pulled the codes for me. All 6 cylinders had misfired. I can understand 3 misfiring, but all 6? The CEL came on about 45 minutes after I got some gas (used highest grade). Any ideas? I know nothing about engines.

Thanks in advance.