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Emission Control System: Purpose

The emission control systems are installed to reduce the amount of CO, HC and NOx exhausted from the engine (3 and 4). they prevent the atmospheric release of blow-by gas-containing HC (1) and evaporated fuel containing HC being released from the fuel tank (2).

The function of each system is shown in the table below.

EMISSION CONTROL SYSTEM FUNCTION

System Abbreviation Function
1. Positive Crankcase Ventilation PCV Reduces HC
2. Evaporative Emission Control EVAP Reduces Evaporated HC
3. Three-Way Catalytic Converter TWC Reduces HC, CO And NOx
4. Sequential Multiport Fuel Injection(1) SFI Injects A Precisely Timed, Optimum Amount Of Fuel For Reduced Exhaust Emissions
(1) For the inspection and repair of the SFI system, refer to FUEL SYSTEMS .