Maytag Dishwasher Not Cleaning Dishes — Fix It Fast

Common Symptoms

• Food particles or grease left on dishes after a full cycle
• White chalky film or spots on glasses and plastic items
• Dishes feel grimy or have a soap residue
• Lower rack items are clean but upper rack items are not
• Dishwasher runs through cycles but water seems insufficient

Most Likely Causes

1. 1

   Clogged Spray Arm Holes — Most Common

   Maytag MDB-series dishwashers have a lower spray arm, an upper spray arm under the top rack, and a middle spray tube. The small holes in these arms clog with mineral deposits, broken glass chips, and food debris. When even one or two holes are blocked the water distribution pattern is disrupted and entire rack sections go uncleaned. Remove each arm by twisting counterclockwise or pressing the center tab, then rinse under running water and clear holes with a wooden toothpick.

2. 2

   Dirty or Clogged Filter and Sump

   Maytag MDB-series dishwashers use a twist-lock fine-mesh filter assembly at the tub floor. Food soil, grease, and hard-water scale accumulate in the filter and the sump cavity beneath it, causing recirculated wash water to become contaminated. Dirty water is then sprayed back onto dishes. Maytag recommends cleaning the filter monthly — twist counterclockwise to remove, rinse under warm running water, and scrub gently with a soft brush.

3. 3

   Wrong Detergent Type or Amount

   Using regular dish soap in a dishwasher creates excessive suds that suppress wash action and leave a film on dishes. Dishwashers require automatic dishwasher detergent — either pods, powder, or gel — not hand soap. Hard water areas require extra rinse aid and may benefit from a water softener additive. Overfilling the detergent cup also causes film; follow the fill-line markings for your water hardness.

4. 4

   Incoming Water Too Cold

   Dishwasher detergent is formulated to activate at 120°F. If the hot water supply is set below 120°F, or if the dishwasher is at the far end of a long hot-water line, water arrives too cold to dissolve grease and activate the enzymes in detergent. Run the kitchen faucet until it is hot to the touch before starting a cycle — this purges cold water from the supply line so the dishwasher fills immediately with hot water.

5. 5

   Failing Water Inlet Valve WP8531669

   The water inlet valve controls the flow of household water into the dishwasher tub. A valve with a partially clogged mesh screen or a failing solenoid coil allows too little water to enter, leaving the tub under-filled. Low tub water means the lower spray arm barely submerges and the upper rack receives almost no water pressure. The valve solenoid should read 200–500 ohms on a multimeter; an open or shorted coil requires valve replacement.

6. 6

   Worn Spray Arm Bearing Ring WP99002318

   The lower spray arm spins on a bearing ring at the center hub of the tub floor. When this ring wears, the lower arm wobbles or sits slightly elevated, reducing its spray angle and effectiveness. A worn bearing ring can also allow the arm to contact the tub floor and stop spinning altogether. Inspect the ring for cracks or excessive play and replace if the arm has more than 1/8-inch of vertical wobble.

Quick DIY Checks

1. 1Remove the lower rack and spin the lower spray arm by hand — it should rotate freely with no binding or wobble. Twist it counterclockwise to remove, hold it up to a light source, and verify each spray hole is open. Clear any blocked holes with a wooden toothpick. Reinstall and repeat for the upper spray arm and the middle spray tube (if equipped).
2. 2Locate the twist-lock filter at the center of the tub floor. Grasp the cylindrical filter portion, rotate counterclockwise until it lifts free, then pull out the flat mesh filter beneath it. Rinse both pieces under running warm water. Use a soft brush (an old toothbrush) to scrub away grease and mineral scale. Clean the sump cavity below the filter with a damp cloth. Reinstall — twist clockwise until it clicks.
3. 3Check the detergent you are using. It must be automatic dishwasher detergent — not hand soap. If you use powder or gel, check the fill line. Add rinse aid to the rinse-aid dispenser if the indicator is low. For hard water (>15 gpg hardness) increase rinse aid dosage to the maximum setting.

1. 4Test incoming water temperature: run the kitchen hot-water faucet for 60 seconds and hold a cooking thermometer under the stream. It must reach 120°F minimum. If it reads below 120°F, increase the water heater setpoint. If the heater is already at 120°F but the water runs cool at the kitchen faucet, the dishwasher is at the far end of the line — run the hot tap until hot before starting each cycle.
2. 5Inspect the spray arm bearing ring at the center hub of the tub floor. It is the low-profile plastic ring the lower arm spins on. Rock the spray arm vertically — more than 1/8-inch of play indicates a worn bearing ring WP99002318. Remove the lower arm and pull the bearing ring straight up to replace it.
3. 6Disconnect power and water supply. Pull the dishwasher partially out and locate the water inlet valve at the lower-left front behind the kickplate. Remove the inlet hose and inspect the mesh screen inside the valve inlet port for scale or debris — clean with a small brush. Set a multimeter to resistance mode and probe the two solenoid terminals; expect 200–500 ohms. An open reading (OL) indicates a failed valve — replace with WP8531669.
4. 7Run a hot-water cycle with a dishwasher cleaning tablet (Affresh or equivalent) to dissolve mineral buildup inside the tub and spray arms. For severe hard-water scale, pour two cups of white vinegar into the tub floor before starting the cleaning cycle. Do not combine vinegar and dishwasher cleaning tablets in the same cycle.

Repair vs Replace

Recommended Tools & Parts

• Water Inlet Valve

  Controls water fill into the tub; solenoid-operated valve with mesh inlet screen. Fits most Maytag MDB-series dishwashers.

  $25–$45

  Buy on Amazon →

• Spray Arm Bearing Ring

  Lower spray arm center bearing ring. Replace if the lower arm wobbles or drags on the tub floor.

  $5–$12

  Buy on Amazon →

• Filter Assembly

  Twist-lock fine mesh filter and coarse filter basket for MDB-series dishwashers.

  $15–$30

  Buy on Amazon →

Links are Amazon affiliate links (tag: fixitfastai-20). Prices are estimates.

Related Repairs