P1398 Code - Misfire Adaptive Numerator At Limit Condition
Quick Answer
The P1398 diagnostic trouble code (DTC) indicates that the misfire adaptive numerator has reached its limit. Common causes include Worn out or fouled spark plugs, Faulty ignition coils, Clogged fuel injectors. 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 Worn out or fouled spark plugs, Faulty ignition coils, Clogged fuel injectors.
- 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 P1398 Description
The P1398 diagnostic trouble code (DTC) indicates that the misfire adaptive numerator has reached its limit. In simpler terms, this means that the Engine Control Module (ECM) has detected a repeated misfire condition that has exceeded the threshold set for the adaptive numerator. This code is typically triggered when the ECM detects a high number of misfires over a certain period, which can lead to engine performance issues.
Common Causes of P1398
- Worn out or fouled spark plugs
- Faulty ignition coils
- Clogged fuel injectors
- Vacuum leaks in the intake manifold
- Air intake system issues
Symptoms of P1398
- Rough idling
- Engine hesitation or stumbling
- Decreased acceleration
- Increased fuel consumption
- Check Engine Light illuminated
How to Fix P1398
- Diagnose the specific cylinder(s) causing the misfire using a scan tool.
- Inspect and replace spark plugs if needed.
- Test ignition coils for proper function and replace if faulty.
- Clean or replace clogged fuel injectors.
- Inspect and repair vacuum leaks in the intake manifold.
Cost to Fix P1398
The typical repair costs for addressing a misfire adaptive numerator at limit condition can vary depending on the specific cause of the issue. On average, replacing spark plugs and ignition coils may cost between $100 to $300, while cleaning or replacing fuel injectors can range from $50 to $300. Labor costs can add an additional $100 to $300, with total repair costs potentially ranging from $250 to $900. It's important to note that prices can fluctuate based on the location, vehicle make and model, and the rates of the auto repair shop. It's recommended to consult with a professional mechanic for an accurate estimate based on your specific situation.
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Code P1398 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
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