I can't remember the model of my dishwasher off the top of my head (will check tonight), but it's fairly new (~3 years old).
A few weeks ago, it started leaving a decent amount of detergent behind and not actually washing the dishes. I tried soaking the spray arms in vinegar. I tried pulling apart all the filters/etc at the bottom of the dishwasher and cleaning those. I washed out the dishwasher itself to clear out any residue/gunk.
These days, if I add vinegar, baking soda, and a little dish soap (like Dawn) to the dishwasher detergent, maybe 50% of the time the dishes will be washed and all of the soap (and vinegar, etc) will be washed away. The other 50% of the time, the soap (and all) just oozes down the dishwasher door (on the inside) and the dishes stay cruddy.
I've been using a Cascade liquid detergent but I'm happy to switch to anything that's better.
I've read that I may need to look at the water intake valve, but I'm not 100% sure how to do that.
Any advice/recommendations would be awesome.
UPDATE
I had an appliance repairman come out and confirm the pump was shot. He replaced it and all's well, so thank you for all of your advice and input! :D