I recently had a problem in my 8T 2.0 blowing the throttle servo over and over. One race day I lost 2 in the same day. The epa was good but the servo was hitting the lip on the mud guard causing it to slam and eventually go out. I shaved the mud guard and so far a practice day and a race day on it with out any problems. Check to make sure that the servo case has plenty of clearance as these chassis do flex. Also make sure the throttle linkage is not binding. You should be able to move the card all the way open with the servo not moving by pulling on the end of it. If the action does not feel smooth then adjust where the ball cup is so that the arm is level and works smoothly.