What color should the exhaust smoke be if the engine and combustion are working correctly?

Question

DentroTest · Accepted Answer

If the engine combustion is correct, the gases exiting the exhaust pipe should be transparent or invisible to the naked eye, as the result of perfect combustion is mainly CO2 and water vapor. Meaning of other colors: White Smoke: Normal in winter upon starting (condensed water vapor), but if it is thick and persists when the engine is hot, it indicates a fault (usually coolant entering the cylinders). Gray or Black Smoke: Indicates a rich mixture (excess fuel or lack of air due to a dirty filter) or bad injectors. Blueish Smoke: Indicates the engine is consuming oil.

What color should the exhaust smoke be if the engine and combustion are working correctly?

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