Odd one this, it seems to be temperature related, if i use the turbo a bit the car will feel like she's juddering right about -10 on the boost guage, right at my crusing point you know not going faster nor slower.

Really annoying, yet when i take it easy it isn't there, ive replaced all coil packs with new ones, threw in a set of pfr7b's and fitted a new ecu water temp sensor.

Im running a simtek, can anyone help or has had this themselves?