Why Your Dishwasher Leaves Dishes Dirty – And How to Fix It

1. Clogged Spray Arms

The spray arms are the parts that spin and spray water during the wash cycle. If they’re blocked with food particles, mineral deposits, or debris, the water can’t reach your dishes properly.

How to fix it:

• Remove the lower and upper spray arms (they usually pop out or unscrew).
• Rinse them under warm water.
• Use a toothpick or small brush to clear any clogged holes.
• Soak them in vinegar if you see hard water buildup.

Tip: Clean the spray arms every month to avoid buildup.

2. Dirty or Clogged Filter

At the bottom of your dishwasher, there’s a filter that traps food and debris. If it’s clogged, dirty water recirculates during the wash, and your dishes come out looking worse than before.

How to clean the filter:

• Remove the bottom rack and locate the filter (usually in the corner or center).
• Twist and lift it out.
• Rinse it under warm water and scrub with a soft brush.
• Reinstall the filter securely before starting the next cycle.

Check it weekly—especially if you don’t rinse your dishes before loading.

3. Poor Detergent or Wrong Amount

Not all detergents work the same. Low-quality detergent or using too much (or too little) can lead to residue and spots.

What to do:

• Use high-quality, dishwasher-specific detergent.
• Check the packaging for the recommended amount.
• If your water is hard, consider using a rinse aid to reduce film and cloudiness.

Avoid: Regular dish soap—this can cause over-sudsing and poor cleaning.

4. Overloading the Dishwasher

Cramming too many dishes into a cycle blocks the spray arms and prevents water from reaching all surfaces.

Tips for loading:

• Don’t stack plates or bowls too close together.
• Place larger items on the sides, not in front of the spray arms.
• Face dirty surfaces toward the spray jets.
• Avoid blocking the detergent dispenser.

Running a full load is smart—but make sure it’s not overcrowded.

5. Water Temperature Is Too Low

Hot water is essential for breaking down grease and activating detergent. If the water temperature is below 120°F (49°C), the dishwasher may not clean well.

How to check:

• Run hot water from your sink before starting the dishwasher.
• Use a thermometer to check your hot water—aim for 120–140°F.
• If needed, adjust your water heater settings (but not above 140°F to avoid burns).

6. Broken or Worn Parts

If cleaning doesn’t solve the problem, your dishwasher may have a faulty pump, worn-out motor, or failing heating element.

Signs to look for:

• Spray arms not spinning
• Unusual noises
• Dishes not drying
• Persistent dirty dishes after multiple cycles

If that’s the case, it’s best to call a professional.