P0171 Pontiac -Why does my car shut off while driving and now black smoke comes out of tailpipe

Question

I just changed the throttle possition sensordue to car shuting off while driving and not starting up now it continues and black smoke is coming out of the tailpipe

Answer 1

HI there,

This code is usually an indication of a bad mass air flow sensor. Especially with the black smoke, this means it is running to rich actually which is odd with the lean fuel mixture code. You could try unplugging the maf sensor and see if the car will start and run without running to rich. If it does, replace the maf sensor.