Fuel Injection Control System

Multiport Fuel Injection (MFI) System Inputs And Outputs:

PURPOSE
The Multiport Fuel Injection (MFI) Control System is designed to take inputs from various sensors and decide how much fuel the engine needs.

OPERATION
The amount of fuel injected from the fuel injector, or length of time the valve remains open, is determined by the ECCS Control Module (ECM). The amount of fuel injected is a program value mapped in the ECM memory. In other words, the program value is preset by engine operating conditions determined by input signals (for engine speed and air intake) from both the Crankshaft Position Sensor and the Mass Air Flow Sensor.
In addition, the amount of fuel injection is compensated for to improve engine performance under various operating conditions as listed below.

Fuel INCREASE due to:
^ Warming up the engine
^ Startinging the engine
^ During acceleration
^ During hot - engine operation
^ When selector lever is changed from "N" to "D" (A/T models only)

Fuel DECREASE due to:
^ During deceleration