Sounds like the cruise control (multi-function) switch screwing up. Mine did a similar thing. It accelerated by itself when i put the left turn signal on. T=Make sure the switch is off and see if that cures the problem. If it does, you found the problem
@funinthesun, I walked out to check the Sling this afternoon, and sure as shit, the cruise switch was on. I shudder to think how long it's been in the on position. Like, weeks. I'm going to run the machine through its paces this week with and without it and see if I can get some observations on it. I assume that's not proper operation, so....think it's repairable under warranty?