Correct answer
No dense, persistent visible smoke.
Normally, it should not produce dense, persistent visible smoke. Condensation vapour may be visible during a cold start and disappear as the engine warms; that alone does not diagnose a fault. Persistent smoke may need inspection, and its colour does not uniquely identify the cause: white smoke does not always mean only a cold engine, nor does grey smoke always mean dirty injectors. Follow the manual and seek diagnosis for abnormal emissions.
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Permanent dense grey smoke under all conditions.
No dense, persistent visible smoke.
Permanent dense white smoke under all conditions.
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