7 Reasons Your Dishwasher Isn't Cleaning Your Dishes Properly

Your dishwasher can be a major timesaver. But, if your dishes are still dirty at the end of the cycle, you'll just end up having to wash them again, which ends up costing—not saving—you time. If this keeps happening to you, there are several potential causes that could be in the way of you and sparkling dishes. We asked cleaning experts for the most common reasons why the dishwasher isn't cleaning dishes properly. Find out what they said and what you can do to fix the problem below.

You’re not pre-rinsing your dishes

It can be tempting to throw a dish straight in the dishwasher, especially if you're cleaning up after a big meal or dinner party, but this could have consequences on your machine. If you leave lots of food on your plates, it can get trapped in the pumps and washer arms of your dishwasher, said Mallory Micetich, home expert with Angi. “When this food gets trapped it can prevent your dishwasher from draining properly and the water from spraying properly,” she explained. “While you don’t need to scrub the dishes and use soap, they do need to be rinsed of major debris.” 

You’re loading your dishwasher wrong

Are your glasses spotty or bowls left with remnants of last night’s chili? That might have to do with the way you're loading your dishwasher. “You could be preventing your dishes from coming out clean and it’s best to load dishes based on the manufacturer's instructions,” suggested Micetich. Read the manual for the best configuration of how to load the unit. “This will prevent you from blocking the spray arms,” Micetich added.

Another important note is not to overload the dishwasher racks. “You always want to avoid overloading a machine or stacking dishes, cups, and other items on top of each other,” she said. This can prevent both the dishes on top and underneath from getting clean. “When the dishwasher is overloaded, it can prevent the spray nozzles from reaching all of your dishes, leaving some dirty spots,” she added.

You’re not using the correct settings

Most dishwashers have a few settings to select from, which are based on the size of the load, temperature choices, the length of the wash cycles, and whether or not extra rinses are needed. So, to get the best results, it helps to be strategic in your setting choices. “When you’re loading your dishwasher, consider what you’re putting into it,” recommended Micetich. Did you just eat a Thanksgiving meal? Do you have delicate glass items? Are you putting pots and pans into the dishwasher?

“Get familiar with the different cycles that your dishwasher offers and when to use them,” she said. Again, she suggested reviewing the appliance manual for more direction. “While a dishwasher may be simple to run, you might be surprised by the suggestions that you find in your owner's manual to help guide you to select the correct settings for each dishwashing cycle,” Micetich added.

You’re not using the ideal dish detergent

You may not be giving much thought to the dish detergent you choose, but it can help to be a bit picky to make sure you're using the best option for your needs. Cleaning experts suggest trying several different brands to see what works best with your appliance. 

Once you settle on a brand, there are different types to choose from: liquid, powder, tablets, pods. “When considering what detergent to use for your dishwasher, one of the most important things is going to be not using too much,” cautions Micetich. “If you use too much detergent, it can cake onto your dishwasher and make it run less efficiently over time.” If your dishwasher is designed for tablets or pods, this is a great way to prevent using too much detergent, she said.

You’re not picking the correct water temperature

To make sure that your dishes are really getting clean, the water temperature and pressure are essential. “For the best results, your dishwasher should run at about 120 degrees,” clarified Micetich.  If that water in your machine isn’t running hot enough, it can prevent your detergent from dissolving properly and make it especially tricky to tackle grease, she noted. Additionally, if the water pressure isn’t strong enough the detergent won’t activate properly. “If you feel like the pressure or water temperature in your machine might be off, it’s a good idea to call in a pro to help you troubleshoot the issue,” Micetich said. 

You’re not running the dishwasher at the best time

Since you need the water cycles to be hot to clean and sanitize, it may not be best to take a long shower or run a heavy wash load at the same time as your dishwasher runs. “We recommend not using other hot water appliances while the dishwasher runs to avoid diverting resources,” said Marla Mock, president of Molly Maid, a Neighborly company.

You’re not cleaning your appliance periodically

For your dishwater to run at peak performance, you should clean it about once a month to help maintain it and keep it running properly, advised Micetich. To clean the dishwasher, empty its contents, fill a dishwasher safe bowl with a cup of vinegar, place it on the bottom rack, and run a hot water cycle, she instructed. “Then, you can sprinkle baking soda on the bottom of the dishwasher and run a rinse cycle,” she said. You also want to make sure to clean the dishwasher filter by removing the bottom rack, removing the filter, and then cleaning it with warm water and an old toothbrush to scrub away any caked on residue.

You’re waiting too long to run the machine 

Dirty dishes that remain in the appliance can smell and could be especially unpleasant if the dishes weren’t rinsed before being loaded in the unit. In addition to caked on food on kitchenware, food particles can accumulate in the drain filter, drain hose, spray arm, or elsewhere in the dishwasher, which can cause odors, said Mock. “The odor could be especially rancid if the particles are comprised of fish, eggs, or other strong-smelling foods,” she emphasized. 

So, the longer that you let your dishwasher sit unused, the more moisture and buildup is happening inside of it. “By using the machine regularly you can help to keep it clean and running efficiently,” Micetich with Angi indicated.