AutoCodes – Generic – P1398

P1398 Code - Misfire Adaptive Numerator At Limit Condition

Quick Answer

With the engine running, the Powertrain Control Module (PCM) detects that the Actual Crankshaft Position (CKP) sensor signal level disagreed with the Expected CKP sensor signal level. Common causes include Faulty Crankshaft Position (CKP) Sensor, Crankshaft Position (CKP) Sensor harness is open or shorted, Crankshaft Position (CKP) Sensor circuit poor electrical connection. 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: P1398 indicates Misfire Adaptive Numerator At Limit Condition.
Common causes: Common causes include Faulty Crankshaft Position (CKP) Sensor, Crankshaft Position (CKP) Sensor harness is open or shorted, Crankshaft Position (CKP) Sensor circuit poor electrical connection.
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.

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Code Popularity 16,343

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Aug 18, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
Comments
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Code P1398 Description

With the engine running, the Powertrain Control Module (PCM) detects that the Actual Crankshaft Position (CKP) sensor signal level disagreed with the Expected CKP sensor signal level.

OBDII Code P1398 - Misfire Adaptive Numerator At Limit Condition - AutoCodes.com — P1398 Code - Misfire Adaptive Numerator At Limit Condition

What does this mean?

What are the Possible Causes of the DTC P1398?

Faulty Crankshaft Position (CKP) Sensor
Crankshaft Position (CKP) Sensor harness is open or shorted
Crankshaft Position (CKP) Sensor circuit poor electrical connection
Low cylinder compression

How to Fix the DTC P1398?

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 P1398 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 P1398 code?

Need more information on how to fix the P1398 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1398 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P1398 Audi — Engine RPM Signal TD Short To Ground
P1398 Buick — Wheel Speed Sensor 2 G-Sensor Circuit High Voltage
P1398 Cadillac — Wheel Speed Sensor 2 G-Sensor Circuit High Voltage
P1398 Chevrolet — Wheel Speed Sensor 2 G-Sensor Circuit High Voltage
P1398 Chrysler — Misfire Adaptive Numerator At Limit Condition
P1398 Dodge — Misfire Adaptive Numerator At Limit Condition
P1398 GMC — Wheel Speed Sensor 2 G-Sensor Circuit High Voltage
P1398 Jeep — Misfire Adaptive Numerator At Limit Condition
P1398 Volkswagen — Engine RPM Signal TD 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.