The rapid increase in vehicular activities, coupled with an aging fleet and weak emission control systems in the Niger Delta region, has heightened concerns about deteriorating ambient air quality and its potential health consequences on local communities. Despite the growing number of vehicles in Krakrama Community, there is limited empirical data on the contribution of vehicular fleet emissions to ambient air pollution and the associated human health risks, making it difficult to develop targeted mitigation strategies. This study assessed vehicular fleet emissions, ambient air quality, and associated human health risks in Krakrama Community, Rivers State, Nigeria. A mixed-methods approach was adopted, integrating ambient air quality monitoring, vehicular emission testing, traffic volume assessment, and household health surveys. Results showed that concentrations of key pollutants (PM₂.₅, PM₁₀, SO₂, NO₂, CO, and VOCs) consistently exceeded WHO, NESREA, and USEPA permissible limits in both dry and wet seasons. The dry season recorded the highest pollution levels, with PM₂.₅ reaching 67.8 µg/m³ and PM₁₀ 121.4 µg/m³. Traffic volume analysis indicated that light-duty vehicles (32.3%) and commercial buses (22.8%) dominated road usage. Emission testing revealed that all measured vehicular exhaust pollutants exceeded regulatory standards, particularly NOₓ (9.71 g/km), CO (6.24 g/km), and smoke opacity (76.5%). Older vehicles (>10 years) made up 56% of the fleet and were major contributors to elevated emissions. Pearson correlation analysis confirmed strong positive relationships between traffic volume and ambient pollutant levels, especially PM₁₀ (r = 0.88) and CO (r = 0.83), establishing vehicular traffic as the dominant pollution source. Health risk assessment indicated significant non-carcinogenic risks, with a cumulative Hazard Index of 9.74, far above the acceptable threshold of 1.0. Household surveys revealed high prevalence of respiratory symptoms such as persistent cough (60.3%), eye irritation (56.8%), and headaches (53.0%). Regression analysis identified PM₂.₅ and VOCs as the strongest predictors of adverse respiratory outcomes. The study concludes that Krakrama Community is experiencing severe vehicular emission-driven air pollution with significant public health implications. Urgent interventions, including stricter emission enforcement, fleet modernization, improved road infrastructure, and public health protection strategies, are recommended to mitigate exposure and enhance air quality in the region.