Its a 89 mustang Lx 5.0 auto its all stock except a set of flowys. I just replaced the mass air sensor because it was bad. along with new plugs because it was loading up with carbon when the mass was bad. So now it runs ok and dont miss or nothing but it wont stay idling unless it has a load on it like sitting in gear idiling. It also is blowing oil smoke when it is reved up past 3,000 RPM. What could be the issue? I hooked it to a code reader and its saying the MAP sensor and the TPS sensor so i replaced them and it still does the same thing. WHY?