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Q: Raw fuel smell and jerks at 19 mph after acceleration

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kept getting cylinder misfires aND codes for cat convertor so I replaced all the coils spark plugs and cat during that time my car started to jerk everytI me I hit around 19 mph usually after acceleration from a stop then it started smoking from the tailpipe and jerking really bad took to the dealer they said misfire in cylinder 3 cleaned the wetness on the spArk plug moved the coils around . Car still jerks at 19 mph aND car smell raw fuel occasionally. Took it back they said threw a code for o2 sensor behind left cat , replaced it but still having same issue.

My car has 169000 miles.
My car has an automatic transmission.

Hello, 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. I would suggest having a professional from Your Mechanic come to your home to diagnose and inspect your vehicle.

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