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Q: Mass air flow sensor

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My car will be running fine and then it will suddenly jerk once or twice and then shut off, but then it starts back up afterwards. Why is it doing this? The fuel pump has been recently replaced. I did take it to a shop and they said it could be bad fuel, which led me to buying stuff to put in the gas tank to clean it and then it was fine for a month and then out of nowhere it starts to jerk once or twice and then it may shut off when I stop the car.
My car has an automatic transmission.

What you are describing sounds like a dirty or faulty mass air flow sensor. The mass air flow sensor monitors air intake as it is mixed with fuel prior to being injected into the motor. This sensor relays vital information to the ECM which uses this to make adjustments to fuel supply to the motor. A dirty or faulty sensor can cause an imbalanced air/fuel load to be supplied to the motor which results in an over fueling or under fueling situation depending on the conditions. This type of inconsistent fuel supply to the motor may cause a hesitation, loss of power, a jerking reaction, potentially a bit of black exhaust smoke and typically a strong smell of fuel when this sensor is malfunctioning. I would suggest having a professional from Your Mechanic come to your home to diagnose and inspect your vehicle.

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