[mattylondon]

I'm guessing you may have a faulty suction jet pump.

This is my evaluation from the details you've gave us and my understating of how the fuel supply works. Our cars have two fuel pumps. One fuel pump constantly feeds the engine. When more fuel is needed, i.e. higher engine speed, both fuel pumps feed the engine. The fuel tank does have two sides and under normal driving one fuel pump will be working and emptying its side of the tank more quickly. To compensate for this and to balance fuel evenly there is a suction jet pump that delivers fuel one side to another. This, I'm guessing, may be faulty as you do have fuel remaining in your tank.