Well, this IS a new pump. The engine and all ancillaries lay new-in-box from 2007 until spring this year. And the problem started on flight one and has persisted.
I wondered if maybe the pump was too new, and would settle in. But after several flights the problem was still there.
If it's a faulty pump, why doesn't it do it on ground runs? It quits only in the air and with throttle closed. It will idle as long as you like on the ground.
Anyone think a squirt of WD40 in the pump would help?