I have been having this problem intermittently with my 59 plate Fiesta 1.25, when I start the car and put it into gear the car won't move. I have to rev the engine to above 2k rpm for it to move. Other times it will be fine but I can't think what could be wrong.
Also, when I start the car the 'powertrain' light comes on but goes off with the rest of the lights. I can't remember the light coming on before so I don't know if it is supposed to.