Folks this one really applies to any vehicle but however was a 6N beast in question. Polo has been to Stealership not revving up passed 3000rpm. Anyway looked at it and as mentioned cutting like a rev limiter cutting in too early at 3000rpm. Connect the timing strobe light just to prove that the spark was being cut and sure it was. Ok last call was new ecu!. Checked the wiring to the coil and hall sender all checking out ok. So the ecu really was doing its job. Well the coil on the vehicle was brand new and being over looked because of this. Fitted a test coil and HEY fixed. New coil and all good, so the moral of the story is dont trust new parts, if your gut and diagnosis points at something dont over look it because its shiny and new.
Cheers
Jmac