no, but you will get a CEL if you don't get the CEL eliminator modules. It will also be extremely loud if you already have a catback. My brother-in-law has a 98 cobra with an offroad x pipe and slp catback. It's loud as shit, so loud that he is thinking about getting the on road x pipe. If you get the off road x pipe it will really benefit you to get a programmer and have the car tuned, but it's not required.