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Q: Occasional hesitation and shaking, brakes engage randomly

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While driving at higher speeds, my car occasionally starts hesitating and shaking. I went to the dealer and had the throttle checked along with the transmission and everything seems to be working correctly. However, my brakes seem to be engaging randomly for a brief moment. What could be causing this?

Hello. I suggest to inspect two components for possible faults. It is possible that the accelerator pedal position sensor is improperly translating pedal position which will greatly impact the air-fuel ratio negatively which could cause a hesitation.

I’d suggest getting help from a certified technician who will diagnose your trouble codes with a scan tool capable of reading live data. They can then drive the vehicle and take note of the data from components such as the pedal position sensor, mass airflow sensor, and the throttle position sensor. Each of those sensors could cause a hesitation if faulty because the air fuel ratio will be applied incorrectly. I would also recommend checking the condition of the spark plugs because your concern is likely ignition or air fuel ratio related.

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