Please help.My son's Ofna ultraLX comp keeps trying to run away.We have put new batteries in the radio and the reciever on the car,but still loose control.We tried testing to see if the servo reacts.from several distances and it seems to react fine while the engine is not running.But when he tries to drive it around it does not respond the way it should.It seems to be both steering and throttle but not so bad on the steering.The throttle not responding properly is the big problem.We are fairly new to the hobby and this is my first post,but what a wealth of information on this forum.Please give us some advice on how to test or trouble shoot this problem.

Thanks everyone!
Larry E.