My understanding is the MIL eliminators stop the 02 sensors from throwing a Check Engine Light ..... depending on where you live , and if you have to deal with emissions.....most places just "turn off" the 02 sensors in the tune. So you wouldn't need the MIL eliminators in that instance if you got a custom tune.Do I need a tune if I run a catless x and a catback with the mil eliminators?
Sorry, just reread the question. No the MIL eliminators stop the CEL from coming on, that is their job. So you don't need a tune.
If you have emissions that's still a question if you'll pass.