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Circuit Test D8

NOTE: Enter this test when directed here by Diagnosis By Symptom Test in QUICK TEST procedure.
Fig 1: Octane Adjust Circuit
G108606
NOTE: This test is intended to diagnose the following:
OCTANE ADJUST SHORTING BAR LOCATIONS

Application Location
3.8L SC SEFI Passenger side of engine, next to Self-Test connector.

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.