Hello David, thank you for your question. If the upper spray arm is getting enough pressure to spin quickly and spray the water consistently, I would recommend removing the spray arm and soaking it in warm soapy water. Make sure all of the holes in the spray arm are free of any debris. There is a filter on the unit, so you might also want to remove and clean the filter, part number W10872845. To access the filter, unplug the dishwasher. Open the dishwasher door. Reach in and pull out the lower rack until it is resting on the door, and then remove it and set it aside. Push down on the filter and twist it counterclockwise. Turn the filter until it stops moving, with the tabs released. Pull the filter out of the dishwasher and clean it. I hope this helps!