Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is having trouble getting a good signal from one of the sensors that listens for engine noises. It's like trying to hear a whisper in a noisy room.
This code indicates that the signal from Knock Sensor 4 on Bank 2 is lower than expected, which can affect the engine's performance.
The knock sensor detects engine vibrations caused by detonation (knocking) and sends a voltage signal to the engine control module (ECM). A 'low' circuit condition means the ECM is receiving a lower voltage signal than expected from Knock Sensor 4 on Bank 2, which could be due to a wiring issue, a faulty sensor, or other related problems.
• Check Engine Light illuminated
• Poor engine performance
• Increased fuel consumption
• Faulty knock sensor
• Wiring issues or poor electrical connections
• Faulty ECM
Knock Sensor: A device that detects engine knocking and sends signals to the engine control module.
ECM: Engine Control Module, the computer that controls engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to Knock Sensor 4.
• Test the knock sensor for proper operation.
• Replace the knock sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Socket set
$150 - $400
Moderate
• Toyota Camry
• Honda Accord
• Ford F-150
• Regularly inspect and maintain engine components.
• Ensure proper engine tuning and maintenance.
• Use high-quality fuel to prevent knocking.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Avoid hard acceleration until the issue is resolved.
Check with your vehicle manufacturer for warranty coverage on engine sensors.
Knock sensor codes have been common in vehicles with advanced engine management systems, especially as engines become more sensitive to knocking.
Moderate – While not immediately critical, it can lead to engine damage if ignored.
Driving with a faulty knock sensor can lead to engine damage and may not comply with emissions standards.
• Engine at operating temperature
• Vehicle in a quiet environment to hear knocking
The knock sensor is typically located on the engine block, cylinder head, or intake manifold.
Q: What does a knock sensor do?
A: A knock sensor detects engine knocking and sends signals to the ECM to adjust timing and prevent damage.
Q: Can I drive with a P13D6 code?
A: It's possible to drive short distances, but it's best to fix the issue soon to avoid engine damage.
High-End · Full-system diagnostics
A full-system bidirectional platform aimed at advanced DIY users and professional diagnostic workflows.
Network faults often require full-system access instead of a generic code reader alone.
View on Amazon
Universal · Digital multimeter
A solid entry-level multimeter for voltage, continuity, resistance, and basic electrical troubleshooting.
Helpful for checking voltage drops, grounds, and basic circuit health when modules are not communicating.
View on Amazon
Universal · Wire connectors and repair kit
Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
View on AmazonThese are optional diagnostic tools, not guaranteed fixes. As an Amazon Associate I earn from qualifying purchases.