Catalytic Converter Efficiency Calculator
Use this simple tool to calculate catalytic conversion efficiency by entering the measured concentrations of hydrocarbons (HC) and/or carbon monoxide (CO) in the appropriate boxes. Once you have a number entered in both the “Engine-Out” and “Tailpipe” boxes, click outside the box to calculate the percent reduction in emissions. Clicking the "Clear" button deletes all numbers.
For more details about catalytic converter testing, refer to the AirCare Certified Emissions Repair Manual.