What Causes Smoke from a Vehicle Engine?
2 Answers
Possible causes include a small injection advance angle leading to incomplete combustion. Specific reasons and engine maintenance are as follows: Causes: Minor water leakage in the cylinder liner, water in the fuel, air-fuel ratio imbalance, decreased cylinder pressure, premature injection timing, etc. White smoke during cold starts that disappears as the engine warms up is normal. A malfunctioning smoke limiter on the fuel injection pump can cause black smoke during rapid acceleration, and abnormal operation of the exhaust brake system. Maintenance: Use qualified lubricating oil, maintain coolant at normal levels, regularly clean the radiator, periodically change the oil and filter, and ensure good crankcase ventilation.
Throughout my decades of driving career, I've encountered numerous instances of engine smoke. The most common cause is a malfunction in the cooling system, such as a small hole in a hose or a leaking radiator, where coolant flows onto the scorching engine and instantly evaporates into a puff of white smoke. If the smoke is black, it's highly likely due to engine oil leakage, dripping onto the exhaust pipe or turbo and getting burned, producing smoke. In such cases, don't push the car; the engine can easily overheat and fail, and it might even cause a fire. I remember once on a long drive when the fan belt snapped and the fan stopped working, heat built up and white smoke emerged. I immediately pulled over to check fluid levels and waited for the car to cool down before inspecting the fuses and belt condition. Regular maintenance is crucial—don't slack off. Change the coolant and check pipe seals periodically.
