In the field of road transportation, the majority of the vehicles are powered either by diesel or gasoline engines. These engines are fuelled using fossil fuel, resulting in carbon monoxide, unburned hydrocarbon, nitrogen oxides, and soot emission. The emissions from these engine-powered vehicles are one of the major contributors to environmental pollution [1]. The emission from road transport vehicles accounts for two-thirds of the total emissions recorded from the transportation sector [2]. *Author for correspondence Diesel-based engines are widely used in buses, heavy trucks, commercial light-duty vehicles, and passenger cars as they exhibit higher torque, load-carrying capacity, thermal efficiency, and low maintenance cost compared to gasoline-based engines [3].On the other hand, diesel-powered vehicles emit higher amounts of toxic gases compared to gasolinepowered vehicles [4]. The extent of air pollution caused by the emissions from these vehicles is continuously increasing as the demand for vehicles is increasing with time to meet the requirements of the ever-growing population [5].The emissions adversely affect the environment, resulting in climatic changes. Human health is also adversely affected by toxic emissions [6]. To control the pollution caused by vehicles, pollution control authorities lay out emission norms (revised once every