I have a 2005 Lotus Elise. When using little gas in 1st gear, my car sometimes makes jerky/bucking movements. It's fine if I give it more gas or use other gears. I believe the problem is much more likely to happen during the first few minutes after starting up than after it is warmed up, although this might relate to me rarely operating a slow speeds in 1st after having warmed up. This is a relatively new problem that is becoming worse. Does anyone have ideas of what might be causing it?