Why Isn’t My Dishwasher Cleaning?

It’s one of the most frustrating appliance problems: you load the dishwasher, run a full cycle, and open it to find dishes still covered in food, grease, or a gritty film.

Before you schedule a service call, here are the most common reasons your dishwasher isn’t cleaning, starting with the simple fixes you can check yourself.

1. The 2-Minute Fixes: Water Temp & Loading

Before you take anything apart, check these two “user error” issues. They account for a surprising number of service calls.

• Your Water Isn’t Hot Enough Your dishwasher detergent needs hot water—at least 120°F (49°C)—to properly dissolve and activate its enzymes. If the water isn’t hot enough, grease will simply be smeared around, and the soap may not fully dissolve.
  • The Pro Tip: Before starting a cycle, run the hot water at your kitchen sink until it’s steamy. This “primes” the line and ensures your dishwasher fills with hot water from the very beginning.
• You’re Loading It Incorrectly Your dishwasher’s spray arms must be able to spin freely.
  • Don’t Block the Arms: A tall baking sheet, a large pot lid, or a utensil that has fallen through the rack can easily jam the main spray arm, preventing it from spinning and spraying water.
  • Don’t “Nest” Dishes: Bowls or spoons “nested” together create a barrier that water can’t get through. Give items space to be cleaned.

2. The Most Common Culprit: A Clogged System

If your dishes are coming out with a gritty film or caked-in food particles, the problem is almost always a clog. The dishwasher is “cleaning” your dishes with dirty, recycled water.

Problem A: The Filter is Clogged

This is the #1 cause of a dishwasher not cleaning. Your dishwasher has a filter system at the bottom that catches food. If it’s full, that food just gets recirculated.

How to Clean Your Dishwasher Filter:

1. Locate it: Remove the bottom rack. The filter assembly is usually a round, locking component on the floor of the tub.
2. Remove it: Most filters (like those in Whirlpool, KitchenAid, and Maytag models) are removed with a quarter-turn counter-clockwise. Lift the upper filter out, and then lift out the flat lower filter screen.
3. Clean it: Rinse both filter parts thoroughly under your sink faucet. A soft brush can help remove stubborn or greasy buildup. Do not use a wire brush.
4. Replace it: Place the lower filter screen back, then insert the upper filter and turn it clockwise until it locks firmly in place. An unlocked filter can cause damage to the pump.

Problem B: The Spray Arms are Clogged

The spray arms are what shoot the water onto your dishes. If the small holes are blocked, you’ll have zero cleaning power.

How to Clean Your Spray Arms:

1. Remove the Arms: The lower spray arm usually just pulls straight up. The upper spray arm (under the top rack) may pull out or be held by a plastic locking nut.
2. Inspect and Clean: Take the arms to the sink. Use a toothpick, paperclip, or a pair of pliers to pull out any debris (like seeds or small food bits) stuck in the spray holes.
3. Rinse and Reinstall: Flush the arms with water and reinstall them. Give them a spin by hand to ensure they move freely.

3. When It’s Time to Call a Professional

If you’ve tried all the steps above and the problem persists, you are likely dealing with a failed component. This is the line where a DIY fix ends and you should call a certified technician.

• Faulty Soap Dispenser: The dispenser door isn’t opening, or it’s opening at the wrong time (like during the rinse cycle), so the soap is never used or is washed away too late.
• Failed Water Inlet Valve: The dishwasher isn’t filling with enough water. This results in a weak, sloshy wash that can’t reach all the dishes.
• Failing Circulation Pump (Wash Motor): This is the heart of the dishwasher. If the pump is weak or failing, it can’t send water to the spray arms with enough pressure to clean anything.