General System Description

1990 Mitsubishi Eclipse AWD L4-1997cc 2.0L DOHC TurboSECTION General System Description
The Mitsubishi ECI-MULTI (electronically controlled injection-multipoint) system is designed to maintain emission levels and fuel economy to standards set by government agencies, while providing acceptable driveability performance. The system consists of a control unit, control relay, wiring, sensors and actuators.
The ECU consists of an 8-bit microprocessor, random access memory (RAM), read only memory (ROM) and Input/Output (I/0) interface. The control relay supplies the positive circuit to the EGR and purge solenoids, ECU and injectors. It also supplies the positive circuit to the fuel pump during starting.
The system is also able to perform self-diagnostic procedures and provide back-up functions if certain circuits fail.

SENSORS/INPUTS
- A/C control unit
- Air flow sensor (AFS)
- Barometric pressure sensor
- Battery Voltage
- Coolant temperature switch (A/C only)
- Crank angle sensor
- EGR temperature sensor (Ca. only)
- Engine coolant temperature sensor
- Idle position switch
- Ignition switch
- Ignition timing adjustment connector
- Inhibitor switch (A/T only)
- Intake air temperature sensor
- Detonation (Knock) sensor (Turbo only)
- Oxygen sensor
- Power steering load switch
- Throttle position sensor
- Vehicle speed sensor
- #1 cylinder TDC sensor

ACTUATORS/OUTPUTS
- A/C relay
- Automatic transmission control unit
- Diagnostic check connector
- EGR solenoid (Ca. only)
- Fuel injector
- Fuel pressure control solenoid (Turbo only)
- Fuel pump
- Fuel pump check connector
- Idle speed control servo
- Malfunction indicator light
- Power transistor
- Purge control solenoid
- Self diagnosis check connector
- Wastegate control solenoid (Turbo only)


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