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Lambda & Catalytic Converter Efficiency
CO2 @ 25 mph O2 @ 25 mph HC @ 25 mph
CO @ 25 mph NOx @ 25 mph
Results: Lambda Results: CAT Efficiency

This DCF compensated Lambda calculator is designed for use with Smog Check VIR printouts.
However, the catalytic converter efficiency calculation on this webpage is only a rough indicator and is NOT always accurate.
For actual catalytic converter testing procedures, click here.