I finished installing the 750cc JECS injectors today and swapped over to one of Harry's ecu tunes. Ever since I got it back though Im running super rich because Im getting that strong smell of fuel from my exhaust and also have a eratic/rough idle jumping from 800 to 100 and once or twice sputtering and shutting off. My mechanic suggested a SAFC to help lean out the car and get it back to normal. But is that neccesary or is the ecu tune off?