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2018 FORD FLEX

3.5L V6 EcoBoost•AWD•AUTOMATIC•gas•turbo
3 active safety recalls on this vehicle — view recalls
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Repairs0Labor566Torque3755Fluid9DTC966Battery1Maintenance0Recalls3
P1390low severityPowertrain

Octane Adjust Pin Out of Self-Test Range

on 2018 Ford Flex 3.5L V6 EcoBoost · AWD

What this code means

The octane adjust pin signal is not within the expected range during the self-test. This pin allows the PCM to adjust timing for different octane fuels.

Symptoms

  • Check Engine Light
  • Possible spark knock with low-octane fuel
  • Self-test failure

Common causes

  • Faulty octane adjust shorting bar
  • Wiring issue
  • PCM connector problem

Diagnostic steps

  1. Check octane adjust pin/shorting bar
  2. Inspect PCM connector
  3. Verify proper pin configuration for fuel grade

Repair notes

Check octane adjust shorting bar on PCM connector. Repair wiring if damaged.

Other Powertrain codes on this vehicle

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