My stang is running a little rich could it be the 17 year old o2 sensors? Or might it have something to do with replacement exhaust (headers, h, catback)?
Unless you put on a new throttle body or mass air sensor, it may be the O2 sensors. I would get an adjustable fuel pressure regulator first, then replace the O2s.
Unless you put on a new throttle body or mass air sensor, it may be the O2 sensors. I would get an adjustable fuel pressure regulator first, then replace the O2s.