Stumped and Frustrated with a Holley 670 Hesitation

Oh yeah, one more thing. That spring in there is very important.If it looses its springyness, then the pump cavity might not be completely refilled, or fail to refill rapidly enough.And if the arm was not adjusted for an improperly parked diaphram, then you might have an intermitant idle tip-in problem.I guess it would manifest as a stumble on take off, or hesitation, due to a time delay between tip-in and pumpshot.