Hi, I was wondering if my Mass air flow sensor is defective.

For a while now, my car feels hesitant when driving on 6th gear driving at around 60km/hr. I need to shift down to 4th or 5th for the car to feel okay. At higher speeds the car is fine.

There's not error codes.

If i start the car and then disconnect the mass air flow cable, as described in this video:
YouTube
the car keeps running

Does that mean my sensor is defective? If so, where can I get a new one (i want to avoid ebay if i can).