Food left mostly on the lower rack
Plates and bowls on the bottom come out with stuck-on food while the cycle sounds mostly normal.
Start here: Check the filter, sump area, and lower dishwasher spray arm first.
Dishwasher troubleshooting
Samsung Dishwasher Not Cleaning Dishes
Direct answer: A Samsung dishwasher that is not cleaning dishes is usually dealing with one of four things: a packed filter, clogged spray arm holes, weak water fill, or a wash arm that is not moving water the way it should.
Most likely: Start with the easy physical checks first: pull the filter, clear debris from the sump area, make sure the spray arms spin freely, and look for blocked spray holes. Those are the most common real-world causes.
When a dishwasher still runs but leaves grit, film, or food on dishes, the machine is usually washing with poor water movement instead of no water movement. Reality check: one clogged spray arm can make the whole load look like the dishwasher quit cleaning. Common wrong move: stuffing tall pans in front of the lower spray arm, then blaming the machine.
Don’t start with: Do not start by ordering a pump or control part just because the dishes come out dirty. Most bad-cleaning complaints turn out to be blockage, loading, detergent, or fill problems.
If there is standing water in the bottom,treat this as a drain problem first, because dirty wash water will keep recirculating.
If the detergent pod is still partly intact,check for blocked dispenser opening, short fill, or a spray arm that never reached the soap.
Last reviewed: 2026-04-17
What dirty dishes are telling you
Top rack is much dirtier than the bottom
Cups and glasses up top stay cloudy or gritty while lower rack items do a little better.
Start here: Look for a blocked or split middle or upper dishwasher spray arm, or weak overall water fill.
Detergent pod or powder is still there after the cycle
Soap is caked in the dispenser or the pod is only partly melted.
Start here: Make sure nothing blocks the dispenser door, then check that the dishwasher is filling with enough hot water and the spray arms are actually moving.
Everything has a greasy film or fine grit
The load looks rinsed but not really washed, with residue on many items.
Start here: Suspect a dirty dishwasher filter, clogged spray holes, or wash water that never got enough pressure.
Most likely causes
1. Dirty dishwasher filter and debris in the sump
This is the most common cause when the machine runs through a full cycle but leaves food behind. Water gets recirculated through debris instead of moving cleanly through the spray arms.
Quick check: Remove the lower rack and filter. If you see sludge, paper labels, glass chips, or seeds around the filter opening, clean that out first.
2. Dishwasher spray arms blocked or not spinning
A few plugged spray holes or one arm hanging up on a tall dish can leave whole sections of the load dirty, especially one rack more than the other.
Quick check: Spin each spray arm by hand. It should turn freely and not hit dishes, the rack, or a fallen utensil.
3. Low water fill or restricted water supply
If the tub never fills high enough, the wash pump cannot throw a strong spray. Soap may stay in the cup and dishes come out dull or gritty.
Quick check: Start a wash cycle, let it fill, then open the door. You should see water in the bottom, not just a damp sump.
4. Dishwasher wash pump or spray arm support problem
If the filter and spray arms are clean and the machine fills normally but wash action still sounds weak, the pump may not be building pressure or an arm may be damaged and bleeding off force.
Quick check: Listen during the wash portion. A healthy wash usually has a steady swishing spray sound, not a weak hum with little water slap inside the tub.
Step-by-step fix
Step 1: Check for the lookalike problem first: dirty wash versus bad drain
If old water is left in the tub, the dishwasher can seem like it is not cleaning when it is really failing to drain between phases.
- Open the dishwasher after a completed cycle and look at the sump area in the bottom.
- If you see more than a shallow puddle around the filter area, stop here and treat it as a drain issue first.
- If the tub is mostly drained, move on to cleaning checks.
- Smell the water and tub. Sour, dirty water points to recirculated debris and poor draining or filtration.
Next move: If the tub is draining normally, you have ruled out the most common lookalike and can focus on wash performance. If water is sitting in the bottom, poor cleaning may be secondary to a drain restriction.
What to conclude: A dishwasher cannot clean well if it keeps washing with dirty water or never clears debris out of the sump area.
Stop if:
- Water is high enough to threaten a floor spill when you pull the filter.
- You find broken glass, sharp bone fragments, or anything that could cut your hand.
- The dishwasher is backing water toward the kitchen floor.
Step 2: Clean the dishwasher filter and clear the sump area
This is the highest-payoff fix on a dishwasher that runs but leaves food behind. A packed filter chokes water flow and sends debris right back onto dishes.
- Turn off power to the dishwasher at the breaker or unplug it if accessible.
- Pull out the lower rack.
- Remove the dishwasher filter assembly and rinse it under warm water.
- Use mild dish soap and your fingers or a soft brush to remove grease and sludge. Do not force debris deeper into the opening.
- Look into the sump area for labels, seeds, glass chips, toothpicks, or other debris and remove what you can safely reach.
- Reinstall the dishwasher filter so it seats and locks correctly.
Next move: If the next cycle has stronger spray sound and cleaner dishes, the filter restriction was the main problem. If wash results stay poor, move to the spray arm and fill checks.
What to conclude: A dirty filter was either the whole problem or part of it. If it clogs again quickly, you may also have loading or scraping habits sending too much debris into the machine.
Step 3: Make sure the dishwasher spray arms can actually spray
A blocked or stalled spray arm causes uneven cleaning fast. This shows up as one rack cleaning worse than the other or detergent not getting blasted out properly.
- With the racks in place, look for tall cutting boards, sheet pans, or long utensils blocking the lower or middle spray arm path.
- Spin each dishwasher spray arm by hand and feel for rubbing or wobble.
- Remove visible debris from spray arm holes with a toothpick or by rinsing under warm water if the arm is easy to remove.
- Check for cracks, split seams, or a spray arm that has come loose from its mount.
- Make sure the detergent dispenser door can open fully without hitting a pan handle or oversized plate.
Next move: If the arms spin freely and the next load cleans evenly, the issue was blockage or loading. If the arms are clear and free but cleaning is still weak, check water fill next.
Step 4: Check water fill, incoming hot water, and detergent basics
A dishwasher can sound like it is running normally and still wash badly if it is underfilled, starting with cold water, or using soap that never dissolves well.
- Run the kitchen hot water until it turns hot before starting a cycle.
- Start a normal wash cycle and let the dishwasher fill for the first wash portion.
- Open the door and look at the water level in the bottom. You should see a real pool of water in the sump area, not just a wet floor.
- Confirm the water supply valve to the dishwasher is fully open.
- Use fresh dishwasher detergent and avoid overpacking the dispenser area with large items that block the soap door.
- If you usually prewash heavily with hand soap residue on dishes, cut that back because suds can hurt wash action.
Next move: If hotter start water and proper fill improve cleaning, the machine likely did not have enough usable wash water before. If fill looks normal and the basics are right, the remaining likely problem is weak wash circulation or a damaged wash component.
Step 5: If the basics check out, act on the failed component you actually found
By this point you have ruled out the common no-parts causes. Now the right repair depends on what you saw: a damaged spray arm, a loose or failed float, or weak wash action with normal fill and clean filters.
- Replace the damaged dishwasher spray arm if it is cracked, split, warped, or will not stay mounted.
- Replace the dishwasher float assembly if the tub consistently underfills and the float is stuck, damaged, or not moving freely.
- If the dishwasher fills normally, drains normally, filters are clean, and spray action still sounds weak, stop short of guess-buying major internal parts and schedule service for wash pump diagnosis.
- After any correction, run a normal cycle with a mixed load and check both racks before calling it fixed.
A good result: If both racks come out clean and the detergent fully dissolves, you have the right fix.
If not: If cleaning is still poor after a confirmed spray arm or float fix, the wash pump or another internal circulation problem is more likely and is worth a pro diagnosis.
What to conclude: Once the easy restrictions are gone, poor cleaning usually comes down to a failed wash component or a water-fill control issue.
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FAQ
Why is my Samsung dishwasher running a full cycle but dishes are still dirty?
Most of the time the machine is still running but not moving enough water where it needs to go. A dirty dishwasher filter, clogged spray arm holes, blocked arm movement, or low water fill are the usual causes.
Why are only the top rack dishes coming out dirty?
That usually points to poor spray reaching the upper rack. Check for a blocked or damaged middle or upper dishwasher spray arm, tall items blocking arm movement, or weak overall water pressure inside the tub.
Can a dirty filter really make a dishwasher stop cleaning well?
Yes. A packed dishwasher filter cuts flow and lets food debris stay in circulation. The result is weak spray, grit on dishes, and poor cleaning even though the cycle seems normal.
Why is the detergent pod not dissolving all the way?
Start with the simple stuff: make sure nothing blocks the dispenser door, the wash water is starting hot enough, and the spray arms are actually moving water. A low-fill or weak-spray problem often shows up as undissolved detergent.
Should I replace the wash pump if my Samsung dishwasher is not cleaning?
Not first. Rule out the filter, spray arms, loading, detergent release, and water fill before chasing the wash pump. If those checks are good and wash action still sounds weak, then a circulation problem becomes more likely and is worth a closer diagnosis.