We have a fairly expensive ($800) KitchenAid dishwasher that's about 2
years old.

First of all, the manual says you don't even need to rinse dishes.
Just scrape off the big stuff and put them in. But the dishes come
out crusted with food particles.

So even if we rinse EVERYTHING first, it still happens. The side
rails of the sliding shelves are caked with crud. I used a scrub
brush to clean them off, ran a cycle of vinegar, and even used that
Dishwasher Magic.

Within a week, they are caked with crud again, and the dishes come out
filthy. We have to wash half of our dishes after running them through
the dishwasher!!!

Does anyone know what's causing this and what can be done about it?

Have you tried opening it while it's running to see if the arms are
spinning?

Is there stuff caught at the bottom? There's a grinder there that's
supposed to dispose of food particles by grinding them up. Perhaps
it's not working or it's clogged.

You shouldn't need to pre-rinse, although I've found that if I have
rice on the dishes it sticks to them in the dishwasher.

I presume you're not putting utensils in such a way as to impede the
soap door from opening.

Make sure the water is hot!

wrote:

Does anyone know what's causing this and what can be done about it?

I have a mid-range Kitchenaid & I have to fill the detergent cups to
the top & make sure not to put alot of large pots, etc on the lower
rack or I get them same results.

As the other postes metioned check the spray arms for freedom &
blockage.

Bert

accumulated crud in the drain hose? remove and replace it?