I have a 1/5th scale baja rc. My throttle arms moving but the car won't move or even rev.

About the only thing I can think of that would cause nothing to happen when the throttle linkage moves is the lever on the carb where the linkage hooks on is loose and slipping and not opening the carb. If the carb is opening you should see at least some reaction from the motor. Rev up, choke and die, or something. That's where I'd start anyway.