[dav968]

Hi Jfrahm,
Thank you for the response. That makes a lot of sense. I just went down and loosened the gas cap, and had a small amount of pressure in the gas tank that was released. I'll try driving it today with the cap loose since that's quick and easy. If I still have issue, I'll figure out how to disconnect evap.
One of the items I had done in the shop was replacement of the tank pressure valve as the tank was building up pressure on hot days, and I had to fill tank slowly because of back pressure. Those seem to be resolved now, but I still think this is the right track.
On a side note, I'd love to see a pic of the supercharged 968. That sounds like a fun ride.
Thanks again,
David