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Test KP - Octane Adjust

Enter this test when directed here by a driveability symptom. This test is intended to diagnose only the following systems or components:

Fig 1: Octane Adjust Circuit
G90D13154
TEST PIN WIRE COLOR IDENTIFICATION

Application (Test Pin No.) Wire Color
Pin 46 All Models Black/White

The purpose of the Octane Adjust Shorting Bar is to provide optimum spark advance for the fuel being used. If the vehicle engine detonates (spark knock), REMOVE the Octane Shorting Bar. This retards spark advance about 3 to 4 degrees. If the vehicle continues to detonate, use fuel with a higher octane rating.