Fuel: cars with three yuan catalytic converters must use unleaded petrol. Lead and sulfur in leaded gasoline greatly reduce the catalyst efficiency. Lead is used to harden the catalyst and form a layer of crust, which prevents the exhaust pollutants from reaching the catalyst in time and react with it. Therefore, continuous use of leaded fuels will gradually weaken or eliminate the catalytic conversion ability of catalysts to exhaust pollution. Engine: the average internal temperature of the catalytic converter works well up to 816 degrees Celsius, when the temperature is higher than that, the catalyst will melt or decompose, thereby reducing the operating life of the converter. In the abnormal working state, the exhaust gas in the converter contains an excess of HC and other compounds, which turn the catalytic converter into a catalytic furnace with a high temperature high enough to melt the catalyst. Even when the engine is in good condition and debugged at the same time, it will cause excessive catalyst temperature to its improper use. For example, starting at idle for a long time is the worst way to reduce the life of catalytic converters. The idle time is longer and the engine generates more heat than the normal road speed. Therefore, the motor vehicle with catalytic converter should not exceed 10 minutes idle time. Maintenance: when checking the working conditions of each cylinder, it is better to use the oscilloscope without the short circuit method or to remove the spark plug traverse from the running engine to get out of the fire cylinder. If there is no oscilloscope, the engine will not run more than 30 seconds when the spark plug wire or short circuit is unloaded to check the suspicious cylinder; the car that uses the traditional transmission does not start the cart and applies the standby battery and the cross cable; the abnormal working conditions, such as spontaneous combustion, severe surge, tempering, or repeated stall It should be shut down in time, because these conditions can cause permanent damage to the catalytic converter; the driving vehicle must not cut off the ignition switch; when the engine is intermittent ignition, the starting engine does not exceed 60 seconds.