I was driving my 78 280z and it started backfiring from the intake. Upon researching I figured it could be several things. First thing i replaced was the Throttle Position Sensor and it got a little better but there is still a loss of power with inconsistent idling. I know it is running rich because there is a loss of power. When I pushed the flap on the mass air flow sensor the idile became normal again. So I am trying to conclude if I need a new AFM. Any help and suggestions are greatly appreciated. Thanks