I recently purchased a 2012 Yamaha drive and it is way too fast for our RV park. The speed isn't really a problem, its when I take my foot off the gas, to slow down, the engine shuts off completely so the engine comes on and off making if very jerky. Also reeks of unburned fuel. I tried to adjust the governor both ways but that didn't help. Throttle cable? Any info is much appreciated.