David Horii
The Cause
Most dishwasher odors are caused by dirty plates that have been
sitting for a few days or by food trapped in the filter or on the
tub bottom.
The Cure
If your dishes sit before you start the dishwasher, run a "rinse
and hold" cycle until you're ready to wash. To clean the whole
machine, run an empty cycle with two cups of white vinegar (a
natural odor absorber and neutralizer) instead of detergent.
Remember that your dishwasher is not a garbage disposal: You can
prevent odors by rinsing food off before you load.