Just got it yesterday, used but with brand new motor. Test drove, but only very slow in the parking lot. Got it home and it seems to be (electronically?) limited to 11 mph. If I give it gas to try and go above that, it just stutters. The seat belt is buckled and the light goes off on the dash so it doesn't seem to be that. Also the diff lock is off and it's in 2wd H. Any thoughts? I can't find anything addressing this issue anywhere. Thanks!