Our one-year old Kenmore Ultra Wash dishwasher 665.1374 worked great for 6 months then started gradually cleaning more poorly.

Now most dishes are left with specks of food or grease on them -- baked on due to the heated dry!

The owner's manual wasn't much help -- everything checks out. It seems that a filter or hose is likely clogged. I've taken apart and reassembled dishwashers before, but am hoping that won't be necessary. We're going to try the "vinegar cure" but...

1) what are some likely causes (soap, hot water, etc. all working fine)?

2) how difficult is it to remove the screen, access the pump, etc?

3) any other suggestions?

Thanks!

Do you live on one of those states that banned phosphate detergents? Everyone is complaining there.