There looks to be a small air leak in the annulus of the new H1 input mode cleaner A-B joint (Vertex vented, inner O-ring? outer O-ring?).  1.8 x 10-6 torr for 3 days at the aux. cart when backing a "hung" turbo.  I installed a 55 L/s ion pump to the annulus via a 2" x 40" flex line and it is able to easily match the leak rate (3 LEDs lit in equilibrium).