Dishwasher is leaving soap on my dishes in top rack. Was using a gel soap heard that switching to a powder would solve this problem. Did not work. I also cleaned dishwasher with Tang kool-aid, but did not work either. Help

That seems like it's probably related to the recent ban on phosphates in dishwashing soaps. Quite a number of people have found that their dishwashers aren't working as well and are leaving spots and soap behind now that phosphates are not being used.
A little vinegar may help, but the best answer would be to use a water softener.

Maybe . . . remove the lower rack and invert it. Look for cracked or missing plastic coating, exposed, rusted & possibly "swollen" inner steel rod/wire. If found, remove the upper rack and look for more of the same. What you think is "soap scum" is probably rust and other iron compounds leached by the dish soap out of the rusted steel onto the dishes and the dishwasher interior. The following worked for me . . .

To clean the interior (with both racks removed), set to "No Heat" dry, then "Pot & Pan" wash and allow to fill. Open door, dump in a bottle of "Lime A-Way", close & latch door and allow to complete cycle. This should remove most rust and iron-sulphate deposits from interior. If not, scrub them with Lime A-Way and a ScotchBrite pad, then cycle again.

Racks must be replaced (Viking are very expensive, Asko, Bosch, or other lower racks may fit: check your neighbors' racks for fit), upper rack must be Viking unless you can exact-match the Asko or Bosch equivalent.

Possible fix: remove the loose plastic coating and flaking rust with a knife, ruff plastic coating with ScotchBrite, clean with rubbing alcohol, then treat metal/rust with "rust converter" (hardware or home imp store), wash with soapy water, rinse, then clean with rubbing alcohol, dry fully, coat with "high temp" (orange or yellow) silicone sealant (auto part store), covering exposed metal and a half inch or so over the plastic coating. Let set for a day or two.

A trip through the dishwasher for all your stained stainless, glasses and non-metallic coated or non-metallic decorated dishes with Lime A-Way as above (on new or "rebuilt" racks) should get the metallic scum and rust off them.

You don;t list the make and model number or its aproximate age.
The simpelest cause is switching to an ultra-cheap dry detergent. Recommed you use a name brand powder (like Electrosol or Cascade) Never use gel or tablets, ever.
Check all spray arms for blockages. Now is a good time to remove the filter (non trivial but do-able on most dishwashers.)
Clean empty dishwasher by filling a bowl or large cup with white vinegar and placing it in the dish rack. Run a short cycle with no detergent added. You may need to repeat.
If problems persist, the pump motor is probably failing. Schedule a service call or consider replacement of DW. Good Luck!

the problem is hard water leaving the residue. go to www.dishwasherfilter.com and get the dishwasher filtration system. it will reduce the hard minerals that leave the residue and your dishes will be clean as can be. it is very affordable and fits right under your sink.

Either your dishwasher is not getting the water hot enough to dissolve the powder, or you need to switch brands. Try a liquid/gel type of dishwasher detergent.
Try stopping the washer a few minutes after you start a wash cycle. Open the door -- if there is a lot of steam coming out at you, it's not the water temperature. If there is no steam, your dishwasher is not getting hot water and/or the heating coil is not working.

Hi Dirty Dish gang.
After having 2 appliance repairmen here, I now have the latest scoop on our dishwasher problems, $200 later!
Los Angeles IS currently having hard water issues. Also, all the new cleaning gels etc. are actually a cause of our dishwasher problems.  
So, here is what we need to do:
1. Use Cascade POWDER detergent only.  Make sure is is just "plain" no "scented" or "complete"  or gel, etc. (I have tried a phosphate free powder and gel and this is a cause of our problem as well!) 2. Use Jet Dry in the dispenser (set it to a 2-3 opening) 3. Make sure water is at least 120 degrees 4. Only run dishwasher on "normal" setting.  All others just run it longer, hence causing more water stains. 5. Do not pre-wash dishes! You can knock of chunks with a "non" soapy brush, but don't rinse (the oils actually help to clean the dishes) 6.  Do not wash sponges in dishwasher.
Acid Wash: The repairman just gave my washer an Acid Wash today. It says it is an acid derived from lemon, I got mine from Carters appliance in Torrance, CA for about $19. I am to run a normal cycle with the above mentioned Cascade after this "acid cycle" is finished.
If you are still having problems:
Monthly maintenance: Glass Magic: Buy a box of Glass Magic (near the Cascade)  Use 1 Tbsb in main detergent compartment of dishwasher along with the Cascade, till washer starts working again. White Vinegar: You can run an empty dishwasher with white vinegar once a month.  Fill a bowl with 2 cups vinegar and place on bottom rack.  Then run as a normal cycle...this allows vinegar to disperse slowly.
So far it seems to be working.  Good luck.

The new water-conserving dishwashers, including the LG LDF 7811 are very sensitive to the dishwasher soap that is used.
If you notice white staining beneath the soap dispenser at the end of each full wash and possibly undissolved powder remaining in the dispenser, I recommend you stop using that powder and buy a box of Electrosol or Cascade powder and use it in place of what you currently use. Avoid using gel or tablets in all dishwashers.
I experienced very similar problems with the LDF8812 that I personally own. First step to fix was pulling the filter (10 phillips screws) rinsing the filter as best possible, remove all debris. Replace filter and spray arm.
Place a bowl filled with white vinegar in a bowl on the rack of the empty dishwasher. Run a quick wash cycle to the end.
Look closely at the RinseAid cap inside the door, remove it and turn the little dial to a lower number. Over time, adjust it up if dishes are not drying properly.
Use the dishwasher normally - do not overly pre-rinse the dishes because the food particles are actually used during the wash cycle to help clean the dishes. Also, do not over load the dispenser cup with soap. A Tablespoon will do it. If you run out of the rinse aid, feel free to use white vinegar.

With the LG LDS5811 dishwasher and other water/energy saving dishwashers, they are VERY ineffective with untra cheap powder detergent. Switching to Electrosol or Cascade has solved the problem -- and don't use too much.
If you add a whole house water softener, you will be AMAZED how much better your dishwasher and clothes washer work -- especially if your cut down on the amount of detergent your use.
Oh, never use gel or tablets in your diswasher. Ever.
if the problem with the detergent dispenser not opening is a seperate problem. Recommend you submit a seperate problem/question.
Good Luck!

If you are you using a liquid soap or packets that will be the main problem.If your unit fills with water circulates the water and drains the water,and also heaters are working then you probally need to change to cascade powder soap.The film on the dishes is soap.The unit has so much build up in it that when it gets to the rinse cycle it is rinsing dishes with soapy water.You need to get 2 medium bowls fill both 2/3 up with white vinager,place one in upper rack and one in lower rack and run unit on longest cycle letting the vinager splash out during wash.do this with no soap and no dishes.Having soft water will allow you to use less soap.

Yes
The problem is not enough water presure is hitting the soap dispenser. Probably the top rack of dishes is not getting clean either! look for my post about fixing with CLR and use that see what happens then
Thanks
Kashif.A