P1381
OBD-II Diagnostic Code
Severity: ModerateWhat it means
P1381 is a manufacturer-specific code.
On Honda/Acura, it means the cylinder position sensor detected intermittent signal interruptions.
This causes misfires and rough running.
The sensor, its wiring, or the distributor may be faulty.
Affected Models
- Honda Civic
- Honda Accord
- Acura Integra
- Honda CR-V
- Honda/Acura vehicles with distributors
Common Causes
- Cylinder position sensor failing intermittently
- Distributor cap or rotor worn
- Ignition coil connection loose
- Wiring harness damage near the distributor
- Timing belt stretched affecting sensor position
How to Fix It
-
Inspect the distributor cap and rotor for wear.
Cracks, carbon tracks, or worn contacts cause intermittent sensor signals.
-
Check the sensor wiring for damage.
Wires near the distributor can get heat-damaged.
Look for cracked or melted insulation. -
Replace the distributor cap, rotor, and sensor as a set.
These components wear together.
Replacing all three ensures reliable operation.
Frequently Asked Questions
Is P1381 Honda-specific?
The meaning of P1xxx codes varies by manufacturer.
P1381 means cylinder position sensor on Honda/Acura but may mean something different on other brands.
Does my Honda have a distributor?
Honda models before ~2002 typically have distributors.
Newer Honda engines use coil-on-plug ignition without a distributor.