Ford DTC P1390 – Octane Adjust out of Self-Test Range
DTC P1390 meaning on Ford
DTC P1390 for Ford indicates that the Octane Adjust value is out of the self-test range. This means that the engine control module has detected a discrepancy in the octane adjustment parameter that falls outside the expected range during self-testing.
Ford DTC P1390 symptoms
Symptoms of DTC P1390 on a Ford vehicle may include:
- Check Engine Light (MIL) illuminated
- Engine running rough or misfiring
- Reduced engine performance
Ford DTC P1390 causes
Potential causes of DTC P1390 on a Ford vehicle include:
- Incorrect fuel octane rating used
- Faulty knock sensor
- Issues with the engine control module
Ford DTC P1390 seriousness
While DTC P1390 may not always result in immediate drivability issues, it is important to address this fault to prevent potential long-term engine damage or performance issues.
How to diagnose DTC P1390 on Ford
To diagnose DTC P1390 on a Ford vehicle, a mechanic may perform the following steps:
- Use a diagnostic scanner to retrieve the fault code and freeze frame data
- Inspect the fuel octane rating used in the vehicle
- Check the knock sensor for proper operation
- Inspect the wiring and connections related to the octane adjustment system
How to fix DTC P1390 on Ford
To address DTC P1390 on a Ford vehicle, the following steps may be taken:
- Ensure the correct fuel octane rating is being used
- Replace a faulty knock sensor if necessary
- Repair any wiring or connection issues related to the octane adjustment system
- Clear the fault code and perform a test drive to verify the repair
How to erase DTC P1390 on Ford
To erase DTC P1390 on a Ford vehicle, the fault code can be cleared using a diagnostic scanner. After addressing the underlying cause of the fault, clearing the code will reset the Check Engine Light and allow for a fresh monitoring cycle.
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