Frigidaire Dishwasher - top rack dirty dishes

so i read the article on how this diswasher works. last night i opened up the compartement where the ball is and everything looks normal such as the ball looks OK, all the fins on the impeller look good with no broken fins). is there anything else i was to look at in this area.
So my next trial will be to pull out the dishwasher and clean the screen in the inlet valve.[COLOR=#000000] [/COLOR]
[COLOR=#000000]my question is, do i clean the screen or do i have to replace the whole inlet valve. and if i just clean the screen, is there a trick or something good to use (i.e. clr), and where will i find the screen in relation to the inlet valve.[/COLOR]
[COLOR=#000000]thanks.[/COLOR]
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