The needle valve is stuck in the open position.
Over time, the detergent you use to make the detergent/water solution you mix for the detergent tank may separate from the water. This congealed detergent may accumulate in the tank, hose, wand and in the needle valve. Small particles that come from or through your water lines may lodge in the needle valve.
Back flush to wash congealed detergent and/or accumulated particles out of the needle valve and into the detergent tank where it can be removed. Your Dishmaster will work best if you routinely perform the back flush procedure. Make it a habit to take a few moments and back flush every time your tank runs empty and before refilling.
If the back flush procedure does not correct the problem, the needle valve may need to be cleaned manually or the needle valve or other components of the venturi assembly may be broken, worn or out of position. Refer to instructions for K0264 Needle Valve Repair Kit and K0292 Venturi Assembly