Ok my 02 ep3 bout 5k miles ago it does this fluttering like noise. Its kinda hard to explain. It only does it like after 3k rpms untill bout 5k rpms and it when you half throttle or more and it is getting annoying. My mods are SRI, DC race header and Apexi noir exhaust. You can hear it with windows up and down and sounds like its coming from the engine bay.