sometimes my car decides tht it doesnt want to go over 5mph

Sometimes, my car runs perfectly fine. Other times, it decides that it does not want to go over 5mph and it's super irritating and annoying. One morning it will take me to work, but not want to take me home from work. The lightning bolt symbols flashes when it is only going to go 5mph. My car starts every time, but you can tell when it's going to act up based on the light on the dash and the sound of the car. When you start it and it's messing up it often shakes and sometimes growls. I have taken my car to 3 different shops and none were able to detect the cause of the problem. I have paid so much money trying to get this resolved, but no one is able to fix it!