I have something interesting happening more recently. Upon accelerating while I'm driving around 25-35 mph, say picking up speed after slowing for a light, my car seems to want to go to the next gear but it jumps down real quick and then goes up again as I'm attempting to accelerate. No engine lights at all and if I just get on it from a stop then it doesn't do it at all. Only seems to be at that slow rolling speed as I start to accelerate again. Any ideas what this might be?