AutoCodes – Generic – P1391

P1391 Code - CMP or CKP Signal Intermittent Condition

Quick Answer

The Engine Control Module (ECM) detected the actual Camshaft Position Sensor (CMP) position disagreed with the expected CMP level. Common causes for P1391 include wiring or connector problems, a faulty related sensor or actuator, and control module or calibration issues. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P1391 indicates CMP or CKP Signal Intermittent Condition.
Common causes: Common causes for P1391 include wiring or connector problems, a faulty related sensor or actuator, and control module or calibration issues.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

Save to My Repairs Step-by-Step Diagnostic Guide My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 27,332

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Aug 17, 2019

Description
Step-by-Step Diagnostic Guide
How To Fix
Cost to Diagnose
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P1391 Description

The Engine Control Module (ECM) detected the actual Camshaft Position Sensor (CMP) position disagreed with the expected CMP level.

OBDII Code P1391 - CMP or CKP Signal Intermittent Condition - AutoCodes.com — P1391 Code - CMP or CKP Signal Intermittent Condition

How to Fix the DTC P1391?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1391 code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P1391 code?

Need more information on how to fix the P1391 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1391 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P1391 Acura — G-Sensor Performance Problem
P1391 Audi — Camshaft Position Sensor Bank 2 Short To Ground
P1391 Buick — Wheel Speed Sensor 1 G-Sensor Circuit Performance
P1391 Cadillac — Wheel Speed Sensor 1 G-Sensor Circuit Performance
P1391 Chevrolet — Wheel Speed Sensor 1 G-Sensor Circuit Performance
P1391 Chrysler — CMP Or CKP Signal Intermittent Condition
P1391 Dodge — CMP or CKP Signal Intermittent Condition
P1391 Ford — Glow Plug Circuit Low Input Bank 1
P1391 GMC — Wheel Speed Sensor 1 G-Sensor Circuit Performance
P1391 Honda — G-Sensor Performance Problem
P1391 Isuzu — G-Sensor Performance Rough road sensor
P1391 Jeep — CMP or CKP Signal Intermittent Condition
P1391 Mitsubishi — Intermittent Loose Of Camshaft Position Or Crankshaft Position Sensor
P1391 Saab — Cylinder 1 Misfire Detected Random Fuel Level Low
P1391 Suzuki — G Sensor Rough Road Rationality
P1391 Volkswagen — Camshaft Position Sensor Bank 2 Short To Ground

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.