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Q: Check engine light

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Hi when cheak engine light comes on my car jerks as sune as it turns off it goes mint again there is also a strong gass smell that comes through the car when driving

My car has 250000 miles.
My car has a manual transmission.

Hi There, It sounds like you may have a dirty or failing 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 your mass air flow sensor.

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