Q: it just stop responding when I accelerate, then I will have to switch the key off and on and then it will gain power again .

Most of the time this is something wrong with the throttle body assembly or the throttle pedal module. These two work together to open and close the throttle plate as you push on and let off of the gas pedal. This system replaced the cable that was used in the past. Both of these have position sensors that must be compared to each other. If one fails and the PCM (powertrain control module) sees a difference in the two values, the PCM shuts the car down.

Ideally you will need a scanner and hopefully a code has been set. When you turn the key off and on, you may be resetting these codes, so the best scenario is for a technician to catch the failure in the act which can be quite difficult to do depending on how often this is occurring. I recommend booking a stalling inspection so that a certified professional can test the car and pinpoint the cause of the problem.