The Watergate scandal had nothing to do with "water". It was the actual name of the hotel where the crime took place. "Dieselgate" is a meaningless word.
Spanish has a million good suffixes, but my favorite is "-azo", which means hitting somebody with something. Puppyazo would be a reference to when somebody was hit with a puppy (or when a puppy was hit, or a when a shockingly big puppy was revealed.)
