1997 Nissan Sentra Does Spark Plugs Full Carbon Iit Emits Black Smoke First

1997 NISSAN SENTRA
200,000 MILES
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ANONYMOUS
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why does its spark plugs full of carbon?iit emits black smoke first then white smoke after the engine heats up?
Apr 8, 2013 at 6:49 PM
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KHLOW2008
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Engine is running rich with excessive fuel getting into the cylinders and producing the black smoke.

If smoke is grey, oil is being burnt in cylinders. If it is completely white, you have a head gasket problem and would be having issues with coolant losses and overheating.
Apr 14, 2013 at 10:25 AM
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