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 controlling how much air goes into the engine on one side of the engine. It's like when you can't open or close a door properly because something is stuck.
The P0639 code is triggered when the Engine Control Module (ECM) detects a problem with the throttle actuator control system on bank 2, which may affect the engine's air intake.
The throttle actuator control system is responsible for regulating the amount of air entering the engine. Bank 2 refers to the side of the engine opposite bank 1 in a V-type engine. A range/performance issue indicates that the throttle actuator is not operating within the expected parameters, possibly due to a malfunction or a mechanical issue.
• Check Engine Light is on
• Reduced engine performance
• Unstable or rough idling
• Faulty throttle actuator
• Wiring or connection issues in the throttle control circuit
• ECM software or hardware malfunction
Throttle Actuator: A device that controls the opening and closing of the throttle valve.
ECM: Engine Control Module, the computer that controls engine functions.
• Use an OBD-II scanner to confirm the P0639 code.
• Inspect the throttle actuator and wiring for damage or disconnection.
• Test the throttle actuator control circuit for proper voltage and continuity.
• Replace the throttle actuator if faulty.
• Repair or replace damaged wiring or connectors.
• Update or reprogram the ECM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$150 - $600
Moderate
• Toyota Camry
• Ford F-150
• Chevrolet Silverado
• Regularly inspect and maintain the throttle body.
• Ensure all electrical connections are secure.
• Keep the engine clean to prevent debris from entering the throttle system.
Engine Performance
• Do not ignore the Check Engine Light.
• Avoid driving aggressively until the issue is resolved.
Check with the vehicle manufacturer as throttle actuator issues may be covered under the powertrain warranty.
P0639 is a less common code but can occur in vehicles with electronic throttle control systems, particularly as they age.
Moderate – It is advisable to address this issue soon to prevent further engine performance problems.
Driving with a malfunctioning throttle actuator can lead to reduced engine performance and potential safety risks.
• Engine at operating temperature
• Vehicle in park or neutral
The throttle actuator is located on the throttle body, which is typically mounted on the intake manifold.
Q: Can I drive with a P0639 code?
A: While you may be able to drive, it is not recommended as it can lead to reduced performance and potential safety issues.
Q: How do I reset the Check Engine Light after fixing the issue?
A: You can reset the light using an OBD-II scanner or by disconnecting the battery for a few minutes, but ensure the issue is fixed first.
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