D16y7 i think there is a check light at the ecu on passanger side you can have a look ,see if it blinks for error code...if not mistaken yours is zc engine..if nothing comes out there is no need to adjust...unless you tangan gatal... :)
to all sifu's out there..
Im asking this question on behalf of my brother. is there any subaru specialist in sunway that is capable in doing anything, (modification, repairs, etc.) to an impreza?