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 computer in the car is having trouble with a sensor that helps control parts of the engine that make the car run smoothly. It's like when a toy's remote control isn't working right.
The P266B code is triggered when the engine control module (ECM) detects a problem with the rocker arm actuator position sensor circuit on bank 2. This sensor helps the ECM adjust the engine's rocker arms for optimal performance.
The rocker arm actuator position sensor is responsible for monitoring the position of the rocker arm actuator, which adjusts the engine's valve timing for better efficiency and performance. Bank 2 refers to the side of the engine that does not contain cylinder 1. A range/performance issue indicates that the sensor's signal is outside the expected range or not performing as expected.
• Check Engine Light illuminated
• Engine misfires or runs rough
• Decreased fuel efficiency
• Faulty rocker arm actuator position sensor
• Wiring issues such as open or short circuits
• Faulty ECM
ECM: Engine Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors related to the sensor.
• Test the rocker arm actuator position sensor for proper operation.
• Replace the rocker arm actuator position sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Honda Accord
• Toyota Camry
• Ford F-150
• Regular maintenance and inspection of engine components
• Ensure proper oil levels and quality
• Check wiring and connectors periodically
Sensor Issue
• Do not ignore the Check Engine Light.
• Seek professional diagnosis if unsure.
• Regularly maintain your vehicle to prevent sensor issues.
Check if your vehicle is still under warranty as this may cover the repair costs.
The P266B code has become more common with the advent of advanced variable valve timing systems in modern engines.
Moderate – While the vehicle may still be drivable, it could lead to further engine issues if not addressed.
Ignoring this code may lead to increased emissions and potential engine damage, which could be unsafe and illegal in some areas.
• Engine at operating temperature
• Vehicle in a safe and controlled environment
The rocker arm actuator position sensor is typically located on the cylinder head of the engine on bank 2.
Q: What does Bank 2 mean?
A: Bank 2 refers to the side of the engine that does not contain cylinder 1.
Q: Can I drive with a P266B code?
A: It's possible to drive, but it's not recommended as it could lead to further damage or decreased performance.
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Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
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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.