An unpleasant odor coming from your LG dishwasher can be frustrating, especially if you’ve already cleaned the interior and expected the smell to disappear. While wiping down the tub and running a cleaning cycle may temporarily improve the situation, persistent odors usually indicate that something deeper inside the appliance requires attention. In many cases, the problem is related to a clogged drain filter or standing water trapped in the dishwasher.
Understanding why the odor keeps returning can help you prevent further issues and protect your dishwasher from more expensive repairs.
Why Does an LG Dishwasher Smell Even After Cleaning?
Dishwashers constantly handle food particles, grease, detergent residue, and moisture. If even a small amount of debris remains inside the machine, bacteria and mold can begin to grow, producing unpleasant smells. If you’ve already cleaned the visible parts of your dishwasher but the odor remains, the issue may be hidden within the drainage system rather than the interior itself.Dirty or Clogged Drain Filter
One of the most common causes of persistent dishwasher odors is a dirty drain filter. The drain filter is designed to capture food debris before it reaches the drain pump. Over time, grease, small food particles, bones, seeds, and paper labels can accumulate inside the filter. As this material decomposes, it creates a sour or rotten smell that spreads throughout the dishwasher every time the door is opened. Signs of a clogged drain filter include:- Persistent unpleasant odors
- Slow water drainage
- Food particles remaining after a wash cycle
- Dirty dishes despite using the correct detergent
Standing Water Inside the Dishwasher
Another common reason for bad smells is standing water. At the end of each wash cycle, only a small amount of clean water should remain near the pump to protect internal seals. However, if larger amounts of water stay inside the bottom of the dishwasher, bacteria and mold quickly begin to grow. Standing water often indicates that something is preventing proper drainage. Possible causes include:- Blocked drain filter
- Clogged drain hose
- Drain pump obstruction
- Improper dishwasher installation
- Air gap blockage
- Garbage disposal connection problems
Clogged Drain Hose
The drain hose carries dirty water from the dishwasher to your home’s plumbing system. Grease, detergent residue, and food particles can gradually coat the inside of the hose, restricting water flow. In some cases, the hose may become kinked or partially blocked by debris. When wastewater cannot drain completely, foul odors develop quickly. Professional technicians can inspect the hose and determine whether it requires cleaning or replacement.Mold and Mildew Growth
A dishwasher provides the perfect environment for mold when moisture remains trapped inside. Common areas where mold develops include:- Door gasket
- Lower spray arm
- Drain filter housing
- Water channels
- Bottom corners of the tub
Drain Pump Problems
The drain pump removes dirty water after each wash cycle. If the pump becomes partially blocked by broken glass, food debris, or other foreign objects, water may not drain completely. A failing drain pump motor can also leave water inside the dishwasher, resulting in recurring odors and poor cleaning performance. Ignoring these symptoms can eventually lead to complete drainage failure.Garbage Disposal Connection Issues
If your dishwasher is connected to a garbage disposal, the disposal itself may be responsible for the odor. Food waste trapped inside the disposal can produce strong smells that travel backward into the dishwasher through the drain hose. Additionally, if the disposal was recently installed and the knockout plug was never removed, the dishwasher may not drain properly at all. A technician can quickly inspect this connection and correct the problem.Incorrect Dishwasher Installation
Improper installation may also contribute to drainage problems. If the drain hose lacks a proper high loop or air gap, dirty sink water may flow back into the dishwasher. This backflow introduces food particles and contaminated water, causing unpleasant smells even after cleaning. Correcting installation errors often eliminates recurring odor issues.Preventing Future Dishwasher Odors
Routine maintenance helps keep your LG dishwasher fresh and operating efficiently. Helpful maintenance practices include:- Clean the drain filter every few weeks.
- Remove large food particles before loading dishes.
- Run hot water in the sink before starting a wash cycle.
- Leave the dishwasher door slightly open after use.
- Use dishwasher cleaner regularly.
- Inspect the spray arms for debris.
- Check the bottom of the tub for standing water.