Alright, well i have a p0300 code and my cel light is on and i can hear a misfire through the exhaust. What have done to this car is OTT Stage 2, which includes 60 lbs injectors, ott tune, 2.8 pulley, step colder plugs, cai, centerforce dual friction clutch, zzp s3 heat exchanger. OTT told me that it could be the plugs or the injectors. A couple days ago i pulled the plugs and they were black on the bottom. I called Hitech motorsports and asked them what could be wrong and he said it could be something with the tune. I ordered a scanner a couple days ago as well. I really need to figure out what is wrong here before i want to get it back out on the roads. Also, i have a air fuel gauge and the numbers are bouncing up and down and ott says that is normal for that because of safety precautions. Any help from you guys would be greatly appreciated.