This term refers to the mobility scooters used primarily by the elderly and handicapped.
Larger stores have them available for shopper's convenience and while intended for those in need, they're occasionally used by able-bodied numbskull kids for entertainment.
The usage of "cooter" in this definition is derived from the word "coot," referring to an elderly person.
Well, it was my first time, and I couldn't figure out where the clit was, and suddenly she lets out this cooter pooter and I'm like, "Whoa, what the hell was that?" It was crazy, man.