If that is done (revs up and down by itself) when your IAC is disconnected and your foot is just on the accellerator then there is a good chance it is a vacuum leak somewhere else. If the revs dropped and then came up again to say 600rpm then adjust the idle speed screw on the throttle body so the idle is really really slow, just above stalling and constant (screw it right in and then about 1/2 a turn out is usual set position). Then do the ECU reset and plug the IAC back in before starting.

An IAC is about $400 retail from Honda for a B16A so I hope it is not that. If you undo the bolts holding on the IAC (two bolts). Pull it away from the manifold so you can see the plunger. Then turn the ignition to the on position and plug the IAC in while watching what is happening. The plunger should move as soon as you plug it in and it will let out a low continuous groan/hum sound. If it does this it may still be okay.