Dishwasher not getting water.

Yesterday, my older GE dishwasher, model GSD2000Z02AD, was giving off a burning type of smell after having run for about 15-20 minutes. Nothing was in contact with the heating elements. The dishes were still dry, the soap lid had popped...didnt see if there was any water at the bottom of the tub. I have noticed that occasionally, there is a small to moderate amount of water leakage from the bottom on the floor. I tried again today, listening closely for normal operation...heard water coming into the unit, then to the spray arms...opened up the dishwasher, dishes are wet and the unit seems to be working. I use this on a regular basis. What gives?