After using the car for a few weeks, today I went to a new circuit, with very little grip. I though at first that the battery voltage was low, but I wasn,t. I even tried another Lipo battery and it happen the same thing again. The car suddenly stops, and after 2 seconds or 1, it works again, anbd then again it stops..It happened suddenly, not problems at all before...Any idea what this could be? I have broken a Ko Propo speedo two weeks ago and I would not want to have another one broken..