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Q: When accelerating, the sound is different

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When accilerate car at slow race the car exhaust make different noises and black smoke. Is it becomes of bad spark plugs?

My car has 10 miles.
My car has a manual transmission.

A: Hi there. Heavy black smoke is usually a si...

Hi there. Heavy black smoke is usually a sign of a rich fuel condition present in your car’s engine. When this happens, the motor is receiving more fuel than it can otherwise burn during the regular combustion cycle. This excess fuel is sent out the exhaust in the form of black smoke as you have experienced. This can happen for many reasons such as a faulty mass air flow sensor, which is what monitors the air intake signaling the ECU to provide more or less fuel. The noise issue might be related to an exhaust leak. To know for sure, you should have a professional mechanic from YourMechanic complete a smoke from engine inspection so they can pinpoint the source of your issues and recommend the right repairs be completed.

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