i hooked up turbo and i still got the engine checklight.. i heard getting a map sensor will take that out? but what is a map sensor... will an exhaust really make my turbo runnning better... befor it was a 2.25 inch piping... with stock axle back( muffler ) im waiting for my thermal 3 inch turbo bak to come ...i hope this will make a diffrence... and will the BOV make a diffrence also... im waiting on the steel flange to come so i can weld it on .... with a stock gsr with GREDDy turbo kit with GREddy intercooler... it suposly said im doing 270 WHP at the greddy 7.5 preset boost... is it really tru? i dont really feeel like i have that much... or its just my car isnt tuned... its running a bit wierd... with the turbo back how much am i prolly gonna gain.. ? sorrie so many questions but this is a forumright? hahhah