ez-go lurches runs 30 yards

[doxneon]

I have a 36 volt cart with problem. I charge cart, then when I step on pedal as soon as micro clicks it lurches dangerously then slows and runs for about 30 yards. if I wait a few minutes it will run slowly a little then nothing. I put in new batts. same thing. I was told to change potentiometer. But have doubts. need advice.