my car likes low to mid 12s at idle (neg split)
under boost they should be no higher than 12ish
should be high 14s low 15s at cruise.
With your 2.0 you should be able to tune most of this. Make sure you didn't turn on weird settings on the rtek on accident.
doublecheck all of your wiring is to the correct pin placement, etc on the ECU and that you are using the wideband 0-5v output (not the narrow band 0-1v) of the PLX.