Monitor Description

Fig 1: Locating MIL Illumination Of ECM

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The ECM illuminates the MIL if the misfiring rate exceeds a threshold value and could cause emissions deterioration.

The ECM will illuminate the MIL when the percent misfire exceeds the specified limit per 1,000 engine revolutions. One occurrence of excessive misfire during engine start will set the MIL. Four occurrences are required to set the MIL 1,000 revolutions after engine start. (2 trip detection logic)

The MIL blinks when percent misfire causing catalyst damage per 200 revolution is met 3 times (1 time if the engine RPM is in high speed range). (MIL blinks immediately)