help with diagnosis

[musketeer180]

Don't know if I'm in the right place for this but I'd be grateful for any thoughts. I have a Japanese import Passat estate 2012, done 46,000 miles. When I am accelerating and particularly if the engine is under load, like going up a hill, the engine warning symbol comes on and if the load increases, the EPC light comes on and the car judders quite violently. However as soon as I turn off the engine it resets and all is well again. I have cleaned the throttle body, which was not dirty anyway and it has been suggested that it is the potentiometer. Any thoughts would be much appreciated.