1994 850 Turbo Wagon

The last four times I have refueled, almost as soon as I get back on the road the car starts to loose power and eventually dies. It'll start back up but won't hold an idle. It throws all kinds of codes having to do with cylinder misfires and once threw a Fuel trim at limits at idle. I'll let it sit overnight and it will start up, hold an idle and after a few miles run just fine. I'll clear the codes and they will remain clear until the next refueling, then, blamo, same thing. I've been consistently letting it get to a quarter tank or less before refueling to keep variables the same. The fuel filter was pulled and poured a glass full of clear clean gas. It doesn't seem to be a fuel delivery problem, rather the engine seems to flood. It spews black exhaust that smells rich with gasoline while it's struggling. Next morning, fine. Theories?