[Russ Ford]

Our dishwasher is not working properly. The top arm is not spinning, thus the dishes are not being cleaned properly. Just a simple troubleshoot, I started the top rack wash only and set the arm in position, waited about ten minutes into the wash cycle, and the arm was in the same position. It did have water dripping down, but apparently not enough to make the arm spin. I believe the amount of water pressure is somehow reduced, thus not causing the arm to spin. Any suggestions???

[denman]

Here are the parts
Replacement parts for FRIGIDAIRE PLDB998AC1 Frigidaire/dishwasher | AppliancePartsPros.com

Here is the tech sheet
http://manuals.frigidaire.com/prodin.../154415101.pdf

Here is a manual that should be close to yours
http://frigidaireservicetips.com/pdfs/484_2.pdf

I am assuming you manually spun the upper arm and it is OK.

Often low pressures are due to dirty filters or junk in the impeller area.
Clean and check.

Sometimes it is because the unit is not filling to the correct level.
Though usually you can hear this as the pump starts to suck in air.
Most units will fill to just under or just over the heating element.
Just under is the most common.
But I do not know which is correct on this unit.
This can be checked by adding a couple quarts of hot water just after it fills.
Just be careful not to overfill it.
If it then washes OK, it is probably a dirty screen filter on the input side of the water valve.