When the engine is cold, or even just warm, the car bunny hops/jumps/porpoises in first and second gears when I start accelerating, even moderately. I really have to treat the accelerator carefully for about five minutes, after which it stops doing it completely and reverts to normal, especially in the higher gears. It doesn't do it at all when the engine is really warm, and accelerates really well. Advice would be much appreciated.
