On 3 separate occassions, upon take-off the tires seem to bounce in place, but car does not move forward. No engine or problem lights are on so not sure what is happening. I took it to the dealership and they told me "the service manager and mechanic drove around in it (my car) for a long time and they didn't notice anything wrong with it". But as I'm driving out of the dealership the car starts to tug!