I have a 01 impreza with the 2.2L with an aftermarket Garrett t25 turbo. I have a stock map sensor and a black box to trick my ecu into not seeing boost. I think it's making my car run a little rough at times like during cruise and when I stomp on the gas it seems to studder then smooth out. I am currently using an Aem fic to tune with but it's hard to try and do myself. My question is should I get a new map sensor that reads boost in the factory location? If so what kind and has anyone ever used an fic before?