I serviced my FL2 (SD4 HSE 2011) recently. It had REP indication and limp mode set, code P006a. Over the next 3 months, 4 garage visits, 2 Sensors, 2 actuators and an intercooler guess what!! on next caravan holiday REP set again. I limped to the nearest layby to reset it. I now keep my OBD 11 monitor installed permanently. They and I have no idea where to go next. Could it be carbon on turbo vanes?