I made a minecart on a track, which moves in a square (9x9), I quited the mine craft, reloaded the map and the minecart with chest suddenly started to move next to the rails and not like straight forward, but a bit sideways, this occured just on the north and the south side of the square and the minecart only moved on the north side of the track, and it only went sideways on like the south of the track, on the north side it went straight forward but on the block north of the track