What emissions result indicates a leaking fuel injector?

In assessing emissions data to identify a leaking fuel injector, it is crucial to focus on the levels of hydrocarbons (HC) and carbon monoxide (CO). A leaking fuel injector typically causes an increase in the HC levels due to unburned fuel entering the combustion chamber, resulting in higher emissions.

The first option shows a HC reading of 200 ppm, which is significantly higher than what's considered normal. This elevated level suggests that there is an excess of unburned hydrocarbons likely due to incomplete combustion resulting from too much fuel being introduced into the engine, a telltale sign of a leaking injector. While the CO level is also elevated at 3.5%, the critical indicator here is the heightened HC concentration.

In contrast, the other options demonstrate lower levels of HC emissions, which would not typically suggest a fuel injector issue. The lower HC levels in those choices indicate better combustion efficiency and less unburned fuel, which most likely rules out any significant fuel leakage from the injectors. Therefore, the data indicating 200 ppm HC aligns with the expected symptoms of a leaking fuel injector.