2009 Smart Fortwo 100,000 miles. Will start and runs good, but after a shrt time if you stop car, it acts like it has gone in neutral; no alarms or indications on panel. Have tried to reset transmission by shutting off car, then push on gas pedal and restart car. Ran fine for about two weeks, then it did it again. Tried to reset transmission again, but after about two weeks it did it again. Dealerships have no clue. Cannot put on analyzer as there is nothing to indicate something is wrong.