1 Get rid of any odor that may be coming from the plumbing pipes your dishwasher shares with the sink. 2  Pour a half a cup of baking soda down each sink drain. 3  Pour cups of vinegar down each drain until all the baking soda is washed away. 4  After 5 minutes, run very, very hot water down each of the drains. Baking soda absorbs odors as the plastic gets hot in the wash. 2  Check the temperature of the water at the sink and make sure you are using hot enough water. 3  You may have to raise the temp on your water heater. 4  Empty all dishes, etc. out of your dishwasher.