I had this problem a few years ago - but on a D100. Almost identical symptoms, and when it came back from a month or more at Melville, the diaphragm actuator and mechanism had been replaced - a rank B2 repair if I recall correctly. I think it cost about $245? I am definitely NOT looking at the receipt. This was back in about 2006 or so.
_____ Brian... a bicoastal Nikonian and Team Member
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