Engine will not accelerate, about once every 20 or so starts. Solved temporarily by switching off and on again. Dealer 'can't replicate the fault'.

Pretty much as I've said above. I start the car, and then either in Drive or Neutral (not tried others) no response even when the accelerator is floored. Car will move, but very, very slowly. I've found that stopping, switching off, waiting and restarting seems to clear the problem. I'm thinking software problem but can't believe I'm the only one. Still within warranty.