That's the first thing I would check. I pulled my intake off to do some work. When I put it back on, I apparently didn't get the throttle mounted back on the same way. When I started it, it was running about 2500 rpm and there was tension on the throttle. Adjusted the cable and it was fine.
Other thing I would check is to see if something is holding the butterflies open. What were you doing, or working on when it started having the issue (have the carb off?)
