Repair help

It could be a possible fault with the idle speed control motor, or more specifically the throttle switch that is integrated into it. It may be indicating that the throttle is at rest when it is not. The result is it seeing the increase in RPM when you accelerate, and wthdrawing the shaft all the way in to try and bring the speed down. The result is the throttle plate slamming shut, and resulting stall. This would also create a hard start, as the airflow is choked off. It would probably start easier with a little pedal apply.