Originally Posted by fotios335i
I hooked up my BT tool to my 335i after removing stage 1 and there wasn't anything there as far as tuner codes. Made me happy as I didn't want to lose the srs system fault.
It's a piggy back tune, so it shouldn't throw any codes as it's not directly connected to CAN or anything else. Stage 1 is just a hijack of certain parameters and word on the street is it shouldn't throw any codes.
Put on DPs and possibly stage 2, and you may get some codes though.