Maytag advises that a new smell is common when you first start to use your dishwasher. Give your dishwasher some time and the odor may subside.
Look through every orifice where gunk from dirty dishes may have accumulated. Check the drain pipe, spray arm, reservoir and any area that could have a buildup. Use paper towels to wipe off any leftover foods in your dishwasher.
If you have used your dishwasher frequently since you installed it, it may be time to change the filter. The odor can be attributed to a dirty filter. Clean your filter according to your Maytag instruction manual.
Your dishwasher could be having drainage problems, resulting in unpleasant odors because residual water is left in the appliance after the cycle. Check that the drain hose is elevated by at least 32 inches. You may have missed this part during the installation process. Also check that the drain hose is free from any kinks. You could also have problems with the drain pipes or your sewer lines. They are likely to require the attention of a plumber.
The smell may also be attributed to your dishwasher detergent. If this is your first dishwasher or you are using a different product, the chlorine in the new product may be causing an unpleasant chemical odor. Swap detergents and see if that does the trick.
A few remedies can fix your Maytag odor problem, regardless of the cause. Add baking soda to the detergent cup on both sides of it. Let the cleaning cycle run for 10 minutes and then unlatch the door and keep it like that overnight. The next day, continue the cycle and let it finish. Run an empty load with 1/2 cup of bleach or 1 cup of vinegar to clean out the dishwasher. Scrub your dishwasher walls with a soft bristle brush.