The steering pulling left or right caused by a dying car battery that affected the electric power steering. Replacing the battery fixed it. However, it shouldn't have happened like that without any kind of warning. It is dangerous.

Car runs fine and can keep straight, but once a while the car can't keep a straight line. If I leave the steering wheel at center, the car would go toward the left, so I have to turn the steering wheel about 30 degree to the right to compensate. It happened about one a week, go away, then come back. The first time it happened, I almost ran over the sidewalk, holy crap, Toyota. Looks like some sensor in the steering system may just go haywire occasionally.