Q: Mass air flow sensor

Hello. The first thing that I would suggest is that you return the mass airflow sensor and get a new one. The mass airflow sensor you installed could be defective causing the same issue you were having previously. Make sure you inspect the intake tube where the mass airflow sensor is attached. Also check the vacuum hoses for leaks or breaks. These two things could also cause the code that you received from the powertrain control module (PCM). The worst case scenario is that the powertrain control module (PCM) is malfunctioning. This is a rare problem, but it is possible, and an extensive diagnosis of the trouble code by a certified mechanic, like one from YourMechanic, would be necessary to make that determination.