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Q: Plugs coming out black but not oilly

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Fuel consumption very high and my spark plugs are becoming black even if i replace new ones
My car has a manual transmission.

A: This is a sign of a rich fueling condition....

This is a sign of a rich fueling condition. This can happen for many different reasons, such as a dirty or failing mass air flow sensor, leaking fuel injectors, a failing catalytic converter or a bad O2 sensor. All of these components are items that when not working properly will cause fueling problems, also resulting in poor fuel economy as well. I would recommend having an expert from YourMechanic come to your location to diagnose your fuel consumption problem.

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