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Q: what can cause high fuel consumption in a 4AGE 1.6GLI

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Spark Plugs has a black velvet soot,with a black smoke from exhaust which smells petrol.(incomplete combustion)

My car has 210000 miles.
My car has a manual transmission.

Hi there:

The black soot on your spark plugs indicates that you’re most likely experiencing a inefficient combustion that is creating more particulate matter (unburned fuel). This could be caused by a vacuum leak, a bad mass air flow sensor or most likely, damage to the EGR valve or other emissions control components. The best way to determine what’s the cause of your poor fuel economy issue, you should have a professional mobile mechanic complete a car is getting poor fuel economy inspection; so they can pinpoint the source of your issues.

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