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Air/Fuel Ratio Learning Control System

By keeping track of or learning feedback control signals sent by the oxygen sensor, the system is able to have the SPFI control unit automatically set a correction. This system stabilizes driveability by maintaining the original performance values through correcting. Thus, the fuel injector always achieves optimum fuel injection under any condition.

CAUTION: Never connect battery in reverse polarity because SPFI control unit will be destroyed instantly and fuel injector and other parts will be damaged in just a few minutes more. Also, DO NOT  disconnect battery terminals while engine is running because a large counter voltage will be generated in the alternator, and this voltage may damage electronic parts such as the SPFI control unit.
Fig 1: SPFI System Schematic
G48342