EGI Control System: Description
The Mazda Electronic Gas Injection (EGI) system monitors various engine/vehicle functions to control engine operation and lower emissions while maintaining good fuel economy and driveability. See Fig 1 .
The Electronic Control Unit (ECU), through various input sensors, monitors battery voltage, engine RPM, intake air volume, cranking signal, crankshaft angle, intake air temperature, radiator and engine coolant temperatures, exhaust oxygen content, throttle position, atmospheric pressure, gearshift lever position, clutch engagement, braking, power steering operation, and A/C compressor operation. The ECU uses this input information in determining spark timing, fuel injection, and the actuation of other output devices.
The ECU has a built-in fail-safe mechanism. If a fault occurs while driving, the ECU will substitute pre-programmed values. Driving performance will be affected, but vehicle driveability will be maintained.