P1391 – Cam/Crank Correlation Fault
Want to confirm the real cause of this fault code?
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Symptoms
- Hard starting
- Stalling
- Misfire
Causes
- Timing chain stretch
- Sensor misalignment
- ECU issue
Diagnosis
- Check cam/crank signals
- Inspect timing components
- Scan ECU
Repair
- Repair timing components
- Replace sensors
- Update ECU