Whirlpool built in dishwasher. not aware of model number

Putting vinegar in the bottom of the dishwasher is not going to help because it has nothing to do with the FILL cycle. The bottom (or sump) actually is used during the WASH and DRAIN cycles. I would check the fill port where the water inlet hose goes into the side of the wash tub. You will need to pull the unit out and locate the inlet hose on the SIDE of the dishwasher. The hose should be a black rubber hose located on the left-hand side of the machine. I had a very similar problem that turned out to be calcium deposits clogging the fill port BEFORE it got to the fill valve. With the unit turned off, I removed the rubber hose and used a small screwdriver to poke straight down into the fill port and break up a bunch of calcium. The unit worked fine after that. It is normal for some dishwasher models to drain if they do not detect enough fill water, or if they detect a leak. Usually when the fill port becomes restricted or clogged you will find puddles of water forming under the dishwasher. You might want to remove the bottom panel and check for leaks as well (if you haven't done so already). If you check the fill port and it is clear, the fill valve could be a possibility as well. However, you mentioned you could hear water running which leads me to believe that you have a simple clog somewhere...but, the valve could have accumulated some deposits as well. Check the fill hose and let me know. Good luck and I hope this helps you. PS Another common mistake people make is to put drain cleaner in their dishwashers. This can damage the pump and chopper assembly. Not to mention, it could be harsh on the some of the rubber seals. Not a good idea.