Q: Car bucks while driving

asked by on December 26, 2016

When cruising at a steady speed, the car bucks. I'm not losing any RPMs

My car has 99000 miles.
My car has an automatic transmission.

Mass Airflow Sensor Replacement $188.36 - $786.53 Get a Quote

Hello There! It sounds like you may have 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. When this is not working properly, you may also notice a strong smell of fuel. I would suggest having a professional from Your Mechanic come to your home to diagnose your mass air flow sensor.

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