I have a new Yahama outboard connected to the original Yamaha binnacle control and cables. At first it seemed to run fine but sometimes when I throttle up the engine past idle speed it loses power and stalls. If I put it in neutral it revs up fine. After restarting and working the control in and out of gear a few times it starts working normally again. I'm thinking it's a problem with the control box or cables rather than the motor. Anyone have any suggestions on how to diagnose this? Thx.