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 thinks the gas pedal or throttle isn't working right. It's like when your game controller button gets stuck and doesn't do what it's supposed to.
The engine control module (ECM) detects that the throttle or pedal position sensor D is not reaching its expected maximum stop position.
The P2166 code indicates that the ECM has detected a problem with the maximum stop performance of the throttle or pedal position sensor D. This sensor is responsible for sending the position of the throttle or pedal to the ECM, and if it does not reach the expected maximum position, the ECM triggers this code.
• Check Engine Light illuminated
• Poor acceleration
• Vehicle may go into 'limp' mode
• Faulty throttle/pedal position sensor D
• Wiring issues or poor connections
• ECM software issues
ECM: Engine Control Module
Throttle Body: A part of the air intake system that controls the amount of air entering the engine
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the throttle/pedal position sensor.
• Test the throttle/pedal position sensor for proper operation.
• Replace the throttle/pedal position sensor D if faulty.
• Repair or replace damaged wiring or connections.
• Update or reprogram the ECM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$150 - $400
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect and clean throttle body.
• Ensure all electrical connections are secure.
• Perform periodic ECM updates.
Sensor Issue
• Avoid driving the vehicle until repaired to prevent further damage.
• Consult a professional mechanic for a proper diagnosis.
Check if the vehicle's powertrain warranty covers sensor replacement.
This code has been associated with throttle position sensor failures in various vehicle models.
Moderate – Should be addressed soon to avoid drivability issues.
Ignoring this code may lead to reduced vehicle performance and safety hazards.
• Engine running
• Throttle fully opened and closed
The throttle/pedal position sensor is typically located on the throttle body or near the accelerator pedal.
Q: Can I drive with a P2166 code?
A: It's not recommended, as it can lead to poor performance and safety issues.
Q: How can I reset the P2166 code?
A: Fix the underlying issue first, then use an OBD-II scanner to clear the code.
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