Super old thread I know but I am having the same issue with one of my sidewinder sct controllers. I only run lipo and even with a 50c pack it will only run if I pick up the car and feather the throttle or sometimes if I give it a rolling start. I pulled it out of the car and tried it with several other motors and even a mini motor and it's the same thing. Even with no pinion I have to really ease on the throttle to make it go. Once it's going it's fine it just won't start. I tried changing the timing, adjusting the punch control and even different battery voltage but nothing works. Any ideas?