Though I use my dishwasher only once a week or less, it requires periodic cleaning like everything else.
I do my best to save water so I rarely rinse dishes before I put them in there, can you say 'redundant' ! I just make sure there isn't a bunch of food on the dishes and I pour the coffee and drinks down the kitchen sink drain of course.
I pack it so full and carefully I can sometimes go weeks before running it -
(which means I have a lot of dishes and sometimes use them twice) - it's a bachelors life sometimes around here !
Step 1: Ugh - What's That Smell ?
Recently I opened my dishwasher to find a hideous odor coming from within -
Truthfully I noticed the smell before coming from the Garbage Disposal the last time I ran the dishwasher but I ignored it - just being lazy I guess.
It was time to investigate so I went in and removed two long screws which held a 'plastic filter' on top of the drain on the back right bottom of the machine - ( one screw is circled in the picture )
I then discovered why water was beginning to pool in the bottom too - YUK ! It was from grease build up over time ( a long long time ) and the grease formed a 'circular dam' around the drain - trust me you don't want pictures of that !! eeeewwww !! I used the usual stuff to clean everything - soap / hot water / vinegar / a little baking soda / your mileage may vary .
I also took out the corner rubber pieces at the bottom of the door - they're removable by just pulling upwards on them ! I also cleaned the underside of the door too. You'll have to stick your whole head in there to see that - it wasn't so nice either !
One other area I noticed that had gotten clogged was the ends of the spinner bar - sunflower seeds ? I wasn't sure how they got in there but that's what was clogging up the end holes....
I removed the 'filter' and cleaned all of that gunk / re-assembled / and ran the dishwasher again with a few minimal dishes just to get it all flushed out - no more water pooling on the bottom afterwards !!
Step 2: A Note on Performance *
For all of us who don't have the Cadillac of dishwashers - ( meaning a top spinner bar & other stuff ) here's a good tip - if you have a simple dishwasher the inside circle of the bottom spinner contains a 'post' or 'column' which 'pops up' when the water pressure is pushing it during a wash or rinse cycle. Since this is the only way that water can get to the top of the dishes ( glasses ) in the top rack, try this:
'LEAVE THE CENTER AISLE OF THE TOP RACK EMPTY'
you find that you won't have a bunch of particles on top of your glasses anymore, because the rinse water can hit the 'ceiling' of the machine and splash back down to rinse everything correctly - experiment - your mileage may vary.
I know people who have those expensive dishwashers and because of the way they load them ( big bowls face down on the bottom rack !?!? ) they still get terrible results - the racks are usually designed so plates are placed vertically in the lower rack - the bottom spinner shoots them with water and then that same water shoots up to the top rack too ! It gets crazy in there !
If you examine the way your dishwasher's 'piping' runs, you'll probably be able to figure out how to put your dishes in there so the water has a chance to 'go everywhere' and that's what really makes things work in there.