run away truck

first off, step on the clutch if the motor runs away. Does that have an electronic throtal? If not, something is prob bad in your throttle cable. Jake comes on when you step off the throttle. Something is giving a signal of no throttle but insted flooring it.

 

I had something like that but not exact happen in an international truck. The speedometer would go nuts and other warning lights would flash and beep. Turned out the it had a faulty wire/connection for the speedometer cable. Also had a loose ground and grease on the speedometer connector. This may be a stretch but I hope it helps.