This problem can also be associated with dirt or grit on dishes and is pretty much the same issue in most cases.
Particles of matter, often looking like grit or sand or may look as if the soil has not been properly removed. There may be re-deposition where foods are deposited on items that did not originally have dirt on them.
This is not a fault with your dishwasher and no service or repair will resolve the problem unless there is a problem with the dishwasher spray arms or the recicrculation motor but, if that is the case it is nomrally very obvious and we strongly suggest that you follow the advice below before placing a service call.
Poor Cleaning Or Your Dishwasher Not Cleaning Is Usually Caused By:
Short wash cycle used
Too low water temperature
Old or badly stored detergent
Food residue in the filters (dirty filters)
Poor quality detergent
Connecting the dishwasher to a hot supply
Adding items to the dishwasher during the wash
Blocked spray arm
Spray arm obstructed
Normally this is the result of food particles being redeposited on the items during the main wash and subsequently not being removed because the water spray does not reach the soiled areas.
Using cycles that are too short or cool as well as not using the correct detergent, poor quality detergent or old detergent can cause this to happen.
It is important if this problem occurs, to check that the spray arms of your dishwasher are clear, clean and can rotate freely. It may also be an indication of a problem with the main recirculation pump in some manner. Also a "not heating" fault with your dishwasher can cause this to occur.
If the filters are not clear and clean the likelihood of this problem is greatly increased.
Connecting the dishwasher to a hot supply is extremely likely to shorten the program cycle which will cause the enzyme in the detergent to decompose too early and will result in poor wash results.
Rewash the affected items after eliminating the cause as above.
Always follow the manufacturers recommended dosage taking into account the water hardness.
Ensure that the spray arms are clean and that no objects are obstructing them, that they freely rotate.
Ensure that the dishwasher filters are clear.
Place tall glasses halfway between the front and back of the dishwasher basket as this exposes them to the best spray pattern.
Ensure that the dishwasher is connected to a water supply that will not exceed about 40?C although we strongly recommend that, for best results, that your dishwasher is connected only to a cold water feed unless the dishwasher is clearly marked as suitable for use on a hot supply.