The answer to 'why is my sump pump making gurgling noise' is that a gurgling sound from your sump pump is usually a sign of a blockage or problem with the pump's drainage system. This can be caused by a clogged or obstructed discharge pipe, a malfunctioning check valve, or low water levels in the sump pit.
A gurgling noise indicates that air is being drawn back into the pump, which can prevent the pump from properly removing water from the pit. This can lead to the pump running more frequently or even failing altogether if the issue is not addressed.