Idle Dip

[Bmatt2020]

While moving at any speed and in any gear, when I shift into neutral to coast, my rpm falls to below my 1000 rpm set-point. It recovers just fine, but it drops low enough that it almost dies. Its more prominent when I have the AC on. Does anyone know what I can do to fix this?

[Spunkster]

What does it idle at with the idle control valve unplugged?