P0386
Crankshaft Position Sensor B Circuit Range/Performance
Crankshaft position
Generic OBD-II
High
What it means
P0386 means the crankshaft position sensor "B" signal is present but out of its expected range or erratic. The ECM uses crank position to time spark and fuel, so a poor-quality signal can cause hard starting, intermittent stalling, and misfires. The engine may still run, but the timing reference is unreliable.
High
Can I keep driving? Risky — an erratic crank signal can cause hard starting, sudden stalling, or misfires, so treat it as unreliable and repair it before relying on the car.
Common symptoms
What you'll notice
- Hard starting
- Intermittent stalling
- Check-engine light on
- Misfire or rough running
- Reduced power
Common causes
Most likely first
- Faulty crankshaft position sensor BLikely
- Damaged reluctor / tone ring or excessive air gapCommon
- Wiring or connector fault in the sensor circuitCommon
- Corroded or loose connectorLess often
- Faulty ECM (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data for the conditions when the signal degrades.
- Inspect the sensor and its air gap to the reluctor ring.
- Check the reluctor ring for chipped or damaged teeth.
- Test the sensor wiring and connector for intermittent faults.
- Replace crank sensor B if the signal is erratic. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0386?+
Not reliably — the erratic timing signal can cause stalling or hard starting without warning. Repair it before depending on the car.
Can I just clear P0386?+
It returns once the ECM re-evaluates the signal; the sensor or reluctor issue has to be fixed.
Related codes
Often seen with P0386
Read & clear P0386 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX