Pollutant emissions such as carbon monoxide (CO), hydrocarbons (HCs), nitrogen oxides (NOx), and particulate matter (PM) from diesel engines have serious adverse effects on both human health and the environment. Advanced post-engine emission control systems, such as the diesel oxidation catalyst (DOC) and selective catalytic reduction (SCR), have proven effective in substantially reducing or minimizing emissions of CO, HC, and NOx. Additionally, the use of metal-based fuel additives in diesel fuel has been widely studied and applied in practice to improve engine performance and optimize emission outcomes. The interaction between metal-based fuel additives and the performance of DOC and SCR systems has become a key area of research focus. This study investigates the impact of metal-based fu...