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 part that controls how much air goes into the engine is stuck and can't move. It's like when a door gets jammed and won't open or close.
The throttle valve controls the amount of air entering the engine. If it's stuck, the engine may not run properly.
The P1639 code indicates that the throttle valve position control system has detected that the throttle is stuck in one position and cannot adjust as needed. This can affect engine performance and emissions.
• Check Engine Light is on
• Poor acceleration
• Engine stalling or rough idle
• Faulty throttle body
• Wiring issues or poor connections
• Malfunctioning throttle position sensor
Throttle Body: A component that controls the amount of air entering the engine.
Throttle Position Sensor: A sensor that monitors the position of the throttle valve.
• Use an OBD-II scanner to confirm the code.
• Inspect the throttle body for obstructions.
• Check wiring and connections to the throttle position sensor.
• Clean or replace the throttle body.
• Repair or replace damaged wiring or connectors.
• Replace the throttle position sensor if faulty.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford Focus
• Chevrolet Malibu
• Toyota Camry
• Regular maintenance and cleaning of the throttle body.
• Routine inspection of wiring and connectors.
• Timely replacement of faulty sensors.
Engine Performance
• Avoid driving the vehicle until repaired to prevent further damage.
• Consult a professional mechanic for accurate diagnosis.
Check with your vehicle manufacturer or dealership for warranty coverage on throttle-related components.
This code has been more common in vehicles with electronic throttle control systems introduced in the late 1990s.
Moderate – Should be addressed soon to avoid potential engine performance issues.
Driving with a stuck throttle can be dangerous and may lead to increased emissions.
• Engine running
• Vehicle in park or neutral
The throttle body is typically located between the air intake and the intake manifold of the engine.
Q: Can I drive my car with a P1639 code?
A: It's not recommended as it can lead to poor engine performance and safety issues.
Q: How can I prevent the throttle from sticking?
A: Regular maintenance and cleaning of the throttle body can help prevent sticking.
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