If your dishwasher isn't cleaning well, check the filter first. A dirty or poorly seated filter can leave grit on dishes, cause odors, and make the dishwasher seem worse than it is.
Start with the filter
Many modern dishwashers have a removable filter at the bottom of the tub. Remove the lower rack, twist out the filter according to the manual, rinse it under warm water, and gently brush stuck debris.
Seat it carefully when reinstalling. If the filter isn't locked in place, cleaning can get worse.
Check the spray arms
Spray arm holes can clog with food debris or mineral scale. Make sure the arms spin freely and aren't blocked by tall pans, cutting boards, or utensils.
If the holes are clogged, clean them according to the manual. Don't enlarge the holes or damage the arm.
Look at loading
Dishwashers need clear water paths. Bowls stacked over each other, large pans blocking spray, and utensils nesting together can all leave dishes dirty even when the machine is working.
Load so dirty surfaces face the spray and water can reach the top rack.
Check water temperature and detergent
Dishwashers clean better when the incoming water is hot enough for the detergent and cycle. Run hot water at the sink before starting if your kitchen takes a long time to get hot water.
Use the detergent amount and type recommended for your dishwasher and water hardness. Too much detergent can leave residue. Too little can leave food behind.
Check the drain area
If dirty water remains in the bottom, the dishwasher may redeposit debris. Check for standing water, a clogged filter well, a kinked drain hose, or a blocked air gap if your sink has one.
When cleaning the filter doesn't fix it
If the filter is clean, spray arms are clear, loading is reasonable, and dishes still come out dirty, the issue may be a weak wash motor, bad inlet valve, failing heater, drain problem, or control issue. Leaks, electrical smells, and repeated failures are repair territory.
Good maintenance rhythm
- Monthly: check the filter if you use the dishwasher often.
- As needed: clean spray arms if holes clog or dishes come out gritty.
- Each load: avoid blocking spray paths.
- After poor cleaning: check filter, spray arms, loading, water temperature, detergent, and drain path before replacing the machine.