We went to race last night, his car was the car to beat. Ran well during first 2 heats, in heat 3 the car just stopped. He could still turn the wheels with his controller, but have no power to his wheels. If you turn the car off, then turn it back on it works again for few minutes and then quits again. So we reset the speed controller on the car. Works again for a few then quits. So then he replaces the speed controller upon advice from another racer and the car does the same, works for a few laps then quits. So after the race, we replace the batteries in the controller, he goes about 25 laps fine then the car just quits again, but still has controller of the steering. Anyone have any suggestions of what this could be? Maybe the controller going bad???