What should a smog check inspector be aware of during a visible smoke inspection?

During a visible smoke inspection, a smog check inspector should focus on identifying crankcase smoke because it can indicate issues with engine combustion and air-fuel mixtures. Crankcase smoke is derived from the engine's breather system, where exhaust gases can enter the crankcase when there is excessive blow-by, which is the result of worn piston rings or cylinder walls. This smoke can be a sign of excessive engine wear or malfunctioning components, potentially leading to increased emissions.

In contrast, while oil leaks, excessive exhaust emissions, and transmission fluid leaks can be important factors in overall vehicle condition and function, they do not pertain directly to the specific focus of a visible smoke inspection. The emphasis here is on smoke as an indicator of the engine's internal health and its correlation to potential emissions failures. Through this lens, recognizing crankcase smoke becomes pivotal for inspectors assessing a vehicle’s compliance with emission standards.