Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer has detected a problem with the sensor that listens for knocking sounds in the engine. It's like a microphone that hears when the engine is not running smoothly.
The knock sensor detects vibrations caused by engine knocking and sends signals to the engine control unit (ECU) to adjust timing. A defective sensor can cause incorrect readings.
The P137B code indicates that the engine control module (ECM) has detected a super knocking condition due to a malfunctioning knock sensor. This sensor is responsible for detecting engine knock, which is a form of abnormal combustion that can damage the engine. If the sensor is defective, it may not accurately detect knocking, leading to potential engine performance issues.
• Check Engine Light is on
• Poor engine performance
• Increased fuel consumption
• Faulty knock sensor
• Wiring issues in the knock sensor circuit
• Engine timing problems
Knock Sensor: A device that detects engine knocking and sends signals to the ECU.
ECU: Engine Control Unit, the computer that manages engine functions.
• Scan the vehicle for codes and freeze frame data.
• Inspect the knock sensor and its wiring for damage.
• Test the knock sensor using a multimeter.
• Replace the knock sensor.
• Repair or replace damaged wiring.
• Reset the engine control module (ECM).
• OBD-II scanner
• Multimeter
• Socket set
$150 - $300
Moderate
• Toyota Camry
• Honda Accord
• Nissan Altima
• Regularly inspect engine sensors.
• Maintain proper engine tuning.
• Use high-quality fuel.
Sensor Issue
• Have the vehicle inspected by a professional.
• Avoid driving aggressively until the issue is resolved.
Check with the vehicle manufacturer for warranty coverage on engine sensors.
This code has been associated with vehicles experiencing repeated knock sensor failures due to poor wiring harness conditions.
Moderate – Addressing this issue promptly can prevent engine damage.
Ignoring this code can lead to engine damage, which may not be covered by warranty if neglected.
• Engine at operating temperature
• Vehicle on a level surface
The knock sensor is typically located on the engine block, cylinder head, or intake manifold.
Q: Can I drive with a P137B code?
A: It's not recommended to drive for extended periods with this code, as it can lead to engine damage.
Q: How do I reset the check engine light after repair?
A: You can use an OBD-II scanner to clear the codes, or disconnect the battery for a few minutes.
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