Q: Shaking

asked by on January 26, 2017

09 bmw 328i xdrive.... car will shake a little only at 1.5-2k rpms. i noticed its only as it warms up and I've been driving it. expecially going up a steep hill and its only when i hold the pedal just right on it

My car has 85000 miles.

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

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 also recommend checking the ignition coil packs, fuel pressure and other items like fuel injector pulse, spark plugs, etc. I would suggest having a professional from Your Mechanic come to your home to diagnose and inspect your vehicle.

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