Originally Posted by howiedds
its a noise mod, and yes it does trigger a code (not tuner), but should not trigger a check engine light.
IMO, do what you want with your car, i dont think its a waste of time/useless mod, its just preference. If you do it, get a BT cable to clear the code before going to the dealer.
as bmw told me that this is not only for sound it also works for engine to prolong work of engine and also presure so all thing can have later result