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Parts for GE GSD2000G00BB Dishwasher - AppliancePartsPros.com

The float switch should not effect wash performance unless it is not letting any water into the unit. It is just an overflow safety device.

A common problem is the unit not filling with enough water.
Most units fill to just under the heating element.
This can be checked by adding a couple quarts of water after each fill during a cycle.
Just be careful to not overfill it.
If it now washes OK then check the fill valve.

Often if the fill is low you will also hear a growling sound because the pump will cavitate (suck in air).
The most common cause is a dirty screen filter on the input side of the fill valve. Remove the valve from the unit and clean/check the filter.
Do not permanently remove it from the valve as it is there to keep crud out of the valve which could hold it open and cause a flood.

If it still does not fill correctly I would replace the fill valve.

PS: Be sure to shut off the power and the water supply to the unit. Have paper towels etc. handy to wipe up any spilled water. Get a small pan/bowl etc. that will fit under the valve then loosen the input water line let it drip into the container emptying it as necessary. This will minimize the amount of water spilled.

I have ran a full cycle. Still not enough water pressure to knock a dry paper towel out of a cup on the top rack. The towel was barely damp, and still in place in the cup where I placed it.

Immediately after shutting the door to when adding water, the unit drains for about 5 seconds. Then it sounds like it is spinning for about a minute. Next it runs water for almost 30 seconds and starts a the cycle. Is that normal operation?

[COLOR="Blue"]Immediately after shutting the door to when adding water, the unit drains for about 5 seconds. Then it sounds like it is spinning for about a minute. Next it runs water for almost 30 seconds and starts a the cycle. Is that normal operation?[/COLOR]
I cannot say as I do not have a cycle chart for this unit.

[COLOR="Blue"]Is this still the fill valve?[/COLOR]
What is the water level after it runs the water for 30 seconds.
This is when you should add water to see if the fill is not enough.

[COLOR="Blue"] Does this still sound like the fill valve or could I have other issues effecting the proper sequencing of this unit?[/COLOR]
Does not sound like a fill valve problem.
take a look at the wash/drain solenoid (left side of pump).
To see if it is activating when it should not.
Up is wash down is drain.
If I remember the cycle for this unit correctly the unit should drain for a little while at the start of the cycle then the solenoid should move up and the unit should fill. The pump will be on but in a washing configuration. The fill valve should then shut off and the ubin should do the pre-wash (a few minutes). Then the drain solenoid is pulled down. It drains the solenoid then moves up and the unit fills again and does the full wash cycle. This should be half an hour or so. It then drains, the pump turns off and it dries the dishes.
The above is what I think it is bit I am not sure about this.

Your problem sounds like it is a timer problem.