If that doesn't help get you a bottle of Dishwasher Magic at Wal Mart and run it through. It might take two bottles.
A lady from another forum had a Whirlpool that was doing similar to yours(she didnt need a part, just not cleaning well) and she used the dishwasher magic (2 bottles) and it fixed hers.
The Glass Magic may be the same thing also. I would try it and see cause I know the techs here know more than me .
Let us know if it worked.