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Home >> Subaru >> 2012 >> Forester X, Automatic Trans >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Diagnostic Trouble Code (DTC) Detecting Criteria (H4DOTC) >> Diagnostic Trouble Code (DTC) Detecting Criteria >> DTC P0301 Cylinder 1 Misfire Detected >> Diagnostic Method >> 720° Interval Difference Method
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720° Interval Difference Method

DIAGNOSTIC VALUE CHART

Diagnostic value domg 720 = (omg 1 - omg 0) - (omg 5 - omg 4)
Misfire judgment domg 720 > Judgment value → Judge as misfire
Fig 1: Crankshaft Position Speed Graph (720 ° Interval Difference Method)
G04993178Courtesy of SUBARU OF AMERICA, INC.

Judgment Value (Judge that malfunction occurs when the misfire ratio is high in 1000 engine revs.)

JUDGMENT VALUE REFERENCE CHART

Malfunction Criteria Threshold Value
FTP emission judgment value ≥ 20 x 100/2000% in 1000 revs.

Time Needed for Diagnosis:  1000 engine revs.

Malfunction Indicator Light Illumination:  Illuminates when malfunction occurs in 2 continuous driving cycles.

JUDGMENT VALUE REFERENCE CHART

Malfunction Criteria Threshold Value
FTP emission judgment value < 20 x 100/2000% in 1000 revs.

Time Needed for Diagnosis:  1000 engine revs.

JUDGMENT VALUE REFERENCE CHART

Malfunction Criteria Threshold Value
Catalyst damage misfire judgment value ≥ Value of Map 3