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 found a problem with the way it listens for knocking noises in the engine on one side. Knocking is like a pinging sound that can happen if the engine isn't running smoothly.
The engine control module (ECM) performs a self-test to ensure the knock sensor system is functioning correctly. If it detects an offset or deviation in knock control for Bank 2, it triggers the P1378 code.
The P1378 code is set when the ECM detects an abnormality or offset in the knock control system for Bank 2. The knock sensor is responsible for detecting engine knocking and sending signals to the ECM to adjust ignition timing and prevent engine damage. An offset indicates a potential issue with sensor readings or ECM processing.
• Check Engine Light is on
• Poor engine performance
• Increased fuel consumption
• Engine knocking or pinging noise
• Faulty knock sensor
• Wiring issues in the knock sensor circuit
• Faulty ECM
• Engine mechanical problems causing abnormal knocking
ECM: Engine Control Module
Knock Sensor: A sensor that detects engine knocking or pinging
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for the knock sensor on Bank 2.
• Test the knock sensor for proper operation.
• Check for any engine mechanical issues that could cause knocking.
• Replace the faulty knock sensor.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• Address any engine mechanical issues causing knocking.
• OBD-II scanner
• Multimeter
• Wrench set
• Screwdriver set
$150 - $500
Moderate
• Honda Accord
• Toyota Camry
• Nissan Altima
• Regularly check and maintain engine components.
• Ensure proper fuel quality is used.
• Perform regular engine tune-ups.
Sensor Issue
• Avoid driving aggressively until the issue is resolved.
• Have the vehicle inspected by a professional mechanic.
Check with your vehicle manufacturer for warranty coverage on engine components.
This code has been associated with issues in vehicles with aging knock sensor systems or wiring problems.
Moderate – It is recommended to address this issue soon to prevent potential engine damage.
Ignoring this code may lead to engine damage and increased emissions, which could fail emissions testing.
• Engine at operating temperature
• Vehicle in a quiet environment to detect knocking
The knock sensor for Bank 2 is typically located on the engine block, cylinder head, or intake manifold on the side of the engine opposite Bank 1.
Q: What is engine knocking?
A: Engine knocking is a noise that occurs when fuel burns unevenly in the engine's cylinders.
Q: Can I drive with a P1378 code?
A: It's not recommended to drive for extended periods with this code, as it could lead to engine damage.
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Fitment Required · Vehicle-fitment part
Commonly relevant for misfire, ignition-efficiency, and some drivability-related repairs.
Misfire and ignition-related faults commonly involve spark plugs as part of the repair path.
Check the correct plug type, gap, and engine application for your vehicle.
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Fitment Required · Vehicle-fitment part
Relevant when the fault points toward ignition-coil performance or cylinder-specific ignition issues.
Some ignition faults involve coil performance or cylinder-specific coil problems.
Match the coil to your engine and confirm the failed component before ordering.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.