Knock Sensor 2 Circuit Range/Performance (Bank 2)
What does P0331 mean?
The P0331 code means the vehicle's onboard diagnostic system has detected: Knock Sensor 2 Circuit Range/Performance (Bank 2). This is a moderate severity code.
Common Symptoms
- Check Engine Light illuminated
- Reduced power on bank 2 cylinders
- Engine knock or ping under load
- Poor fuel economy
- Sluggish acceleration
Probable Causes (Ranked by Likelihood)
- Faulty knock sensor 2 with degraded output Very High
- Incorrect sensor mounting torque High
- Corroded or damaged sensor connector High
- Engine mechanical noise from bank 2 Moderate
- PCM calibration or software issue Low
Step-by-Step Diagnostic Procedure
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Monitor knock sensor 2 output with a scan tool and compare to knock sensor 1 -- both should respond similarly to tapping
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Verify knock sensor 2 torque matches manufacturer specification
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Check the sensor connector for corrosion, oil contamination, or damage
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Listen for abnormal mechanical noises from bank 2 (rod knock, exhaust leak)
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Replace knock sensor 2 if output is inconsistent or does not respond to stimulus
Frequently Asked Questions
Can I drive with code P0331?
You can drive short distances. The PCM will retard timing on bank 2 as a precaution, causing reduced power and fuel economy. Continued driving without repair is safe but inefficient.
What is the difference between P0330 and P0331?
P0330 is a general malfunction code for knock sensor 2. P0331 specifically means the sensor signal is outside its expected operating range, which can be caused by sensor degradation or incorrect mounting.
Can engine carbon buildup cause knock sensor issues?
Carbon buildup can cause actual engine knock (pre-ignition), which the knock sensor would correctly detect. However, this would not cause a sensor circuit code. Carbon-related knock typically triggers timing-related performance codes instead.