Why Is My Dishwasher Not Cleaning Dishes?

A dishwasher that runs a full cycle but leaves dishes dirty, filmy, or spotted is dealing with one of a few common, fixable issues.

A blocked spray arm. If the spray arm can't spin freely — often because a tall pot or pan is in the way — water simply isn't reaching every dish evenly.

Water that isn't hot enough. Dishwashers rely on hot water to dissolve detergent and break down food residue, so a water heater set too low can quietly hurt cleaning performance.

A clogged filter. Most modern dishwashers have a removable filter that traps food particles, and a clogged one recirculates dirty water instead of cleaning with fresh water.

Hard water mineral buildup. Over time, mineral deposits can coat spray arms and interior surfaces, gradually reducing how well the dishwasher cleans.

Cleaning the filter and checking that spray arms move freely solves this more often than people expect — if it doesn't, the wash pump itself may need to be inspected.