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Engine Controls - Trouble Shooting - No Codes: Overview Infiniti M45 II

DESCRIPTION

The Specification (SP) value indicates the tolerance of the value that is displayed in DATA MONITOR (SPEC) mode of CONSULT-II during normal operation of the engine control system. When the value in DATA MONITOR (SPEC) mode is within the SP value, the engine control system is confirmed okay. When the value in DATA MONITOR (SPEC) mode is not within the SP value, the engine control system may have one or more malfunctions. The SP value is used to detect malfunctions that may affect the engine control system, but will not illuminate the MIL. The SP value will be displayed for the following 3 items

  1. B/FUEL SCHDL - the fuel injection pulse width programmed into ECM prior to any learned on-board correction.
  2. A/F ALPHA-B1 - the mean value of air-fuel ratio feedback correction factor per cycle.
  3. MAS A/F SE-B1 - the signal voltage of the mass airflow sensor.