The objective of the experiment was to observe the behavior of the catalytic converters from cold condition. Usually, this happens about 2 minutes after engine starts and based on this, a transient analysis can be built up to show the variation of main pollutants content over a period of time. However, for this analysis (mainly at idling condition), this range of temperature cannot be reached. As a result, the pollutants reduction or gas conversions were absent. For that reason, a set of recommended transient analysis for the experiment was then transferred to steady-state analysis, where the temperature was risen up to 250oC by increasing the speed and then set back to idling mode to ensure efficient converter operation. However, for uniformity, the cold start consideration was eliminated for both experiment and analysis. The tabulated data were plotted into graphs to clearly indicate the composition of pollutants before and after passing through the catalytic converter over half an hour duration.