Page 105 - Methods For Monitoring And Diagnosing The Efficiency Of Catalytic Converters A Patent - oriented Survey

Toyota Motor Co. Ltd. 87

The sum of the time lags (Tq - Tq)+( T6 - T5) is calculated. If this sum is lower than a
predetermined value the catalytic converter is considered as degraded.

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Fig. 41 (from US508828 1)