INDEPENDENT REFERENCE
White, blue or black exhaust smoke
Smoke color provides clues, not a definitive diagnosis; cold-weather vapor is different from persistent smoke.
Understanding the symptom
Smoke color provides clues, not a definitive diagnosis; cold-weather vapor is different from persistent smoke.
Possible causes to investigate
Blue: oil burning; black: excess fuel/soot; persistent dense white: coolant or unburned fuel depending on engine.
Safe observations
Record color, duration, temperature and any overheating or loss of coolant.
When to stop and get help
Heavy smoke, overheating, fire risk or loss of power means stop safely.
A symptom alone cannot establish a physical diagnosis. Arrange competent inspection where safety is uncertain.