This may be a red herring, but I will tell you about a problem I had with an old Volvo SW. I would make a right turn and it would stall. But being fuel injected with an electric pump it would suddenly start again. The fuel pickup line inside the tank was rusty - mainly from previous owners keeping the tank empty. So when I turned right, the rust hole in the pickup line would draw air. After a few minutes the fuel would cover the hole again and away I went.

I would check your pickup line inside the tank for holes or obstructions that could be a problem when the fuel moves around in the tank. I don't know what kind of strainer is on the pickup, but I also experienced a problem with a customer's car that had water in the tank. The water would block the intake screen. I doubt that is an issue but it might get the creative problem solving juices flowing.

All that being said, most experienced techs will tell you it is almost always the most obvious thing e.g. the float needle.