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 is having trouble with a sensor that listens for knocking sounds in the engine on one side of the car. It's like when you hear a strange noise in your room, but can't find where it's coming from.
The engine control module (ECM) is detecting an issue with the signal from the knock sensor on bank 2, which could mean the sensor is not working properly or the signal is outside expected parameters.
The P135F code indicates that the knock sensor 3 on bank 2 is sending a signal that is out of the expected range or performance. This could be due to a faulty sensor, wiring issues, or other related problems affecting the sensor's ability to detect engine knocking accurately.
• Check Engine Light illuminated
• Poor engine performance
• Increased fuel consumption
• Faulty knock sensor
• Wiring issues or poor connections
• ECM software or hardware issues
ECM: Engine Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the knock sensor.
• Test the knock sensor for proper operation.
• Replace the faulty knock sensor.
• Repair or replace damaged wiring or connectors.
• Update or reprogram the ECM if necessary.
• OBD-II scanner
• Multimeter
• Socket set
$150 - $400
Moderate
• BMW 3 Series
• BMW 5 Series
• BMW X5
• Regularly inspect and maintain engine sensors.
• Ensure proper engine tuning and maintenance.
• Use quality fuel to prevent engine knocking.
Sensor Issue
• Do not ignore the check engine light.
• Have a professional diagnose the issue if unsure.
• Regular maintenance can prevent sensor issues.
Check with the vehicle manufacturer for warranty coverage on engine sensors.
This code is relatively common in vehicles with advanced engine management systems, particularly in performance-oriented models.
Moderate – While the vehicle may still be drivable, ignoring the issue can lead to more significant engine problems.
Driving with a malfunctioning knock sensor can lead to engine damage and increased emissions.
• Engine at operating temperature
• Vehicle driven under various load conditions
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 or pinging, which can damage the engine if not corrected.
Q: Can I drive with a P135F code?
A: While the vehicle may still be drivable, it's best to address the issue soon to prevent potential engine damage.
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