Monitor Description

Fig 1: Communication Diagram Between Camshaft/Crankshaft Position Sensor And ECM

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The ECM illuminates the MIL (2 trip detection logic) if:

• The percent misfire exceeds the specified limit per 1,000 engine revolutions. One occurrence of excessive misfire during engine start will set the MIL. After engine start, four occurrences of excessive misfire set the MIL.

The ECM blinks the MIL (immediately) if:

• The threshold for percent of misfire causing catalyst damage is reached 1 time in 200 engine revolutions at a high rpm, and 3 times in 200 engine revolutions at a normal rpm.
• The threshold for percent of misfire causing catalyst damage is reached.