I think mass air sensor is bad.could a bad o2 sensor be the real problem
hard to say without the 4 digit codes and some diagnostic work. I hate replacing parts just because. Have the car scanned for the codes, your local auto parts store will do it for free in most cases. post the codes back here.
Scan it both are control signals to the computer for air fuel ratio. HEGO is only active after closed loop mode criteria is meet.
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