Wastegate chatter does not exist. Pure and simple. It is purely a term fabricated by those who don't know and mostly the motoring media.

Pet/Mr Cossie 4x4 -

Starturbo - As I said, don't hold me to this as it is not proven. But if you think about it logically, and understand how the system works then it does not make sense that in a perfectly working system chatter can occur (in an ERST with KE-Jet I mean)