Correction Factors

The following factors are used to correct the basic duration of fuel injection in order to make the air-fuel ratio meet the requirements of varying engine operating conditions:

• Air-fuel ratio feedback factor:

  This factor is used to correct the basic duration of fuel injection in relation to the actual engine speed. (See the next section for more details.)

• Start increment factor:

  This factor is used to increase the fuel injection duration only while the engine is being cranked to improve its start ability.

• Coolant-temperature-dependent increment factor:

  This factor is used to increase the fuel injection duration depending on engine coolant temperature signals to facilitate cold starting. The lower the coolant temperature, the greater becomes the increment.

• After-start increment factor:
  • This factor is used to increase the fuel injection duration for a certain period immediately after start of the engine to stabilize engine operation.
  • The increment depends on the coolant temperature at the start of the engine.
• Wide-open-throttle increment factor:

  This factor is used to increase the fuel injection duration depending on the relationship between the throttle position sensor signal and air flow sensor signal.

• Acceleration increment factor:

  This factor is used to increase the fuel injection duration to compensate for a time lag between air flow measurement and fuel injection control for better engine response to driver's pedal operation during acceleration.