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Q: Strong odor of fuel, black smoke on take off, and rough running

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Rough running strong odor of fuel black smoke on take off feels like a motor or trans mount broke but is not

My car has 350000 miles.

A: Hey there. The rough running condition is d...

Hey there. The rough running condition is definitely related to the black smoke and fuel smell which indicates the motor is running rich or being supplied with too much fuel. This can happen for a variety of reasons such as leaking fuel injectors which may leak more fuel into the motor than it can effectively burn. This can also happen when the mass air flow sensor is dirty or malfunctioning causing it to send incorrect signals to the computer which then makes incorrect fueling adjustments. When the oxygen sensors (O2 sensors) are faulty, this can also cause them to send inaccurate signals to the computer which can make incorrect adjustments to fueling causing this kind of condition. I would recommend having a professional from YourMechanic come to your location to properly diagnose your rough running condition so that this can be repaired correctly.

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