Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer noticed that the part controlling how much air goes into the engine got stuck for a short time.
This code indicates that the throttle valve, which controls air intake, was temporarily stuck and did not respond as expected.
The throttle valve is part of the electronic throttle control system. It is responsible for regulating the amount of air entering the engine. When the throttle valve doesn't move as expected, it can cause performance issues. Code P1638 indicates a temporary issue with the throttle valve's movement on Bank 1.
• Engine hesitation or stalling
• Reduced engine performance
• Check Engine Light is on
• Dirt or debris in the throttle body
• Faulty throttle position sensor
• Electrical issues in the throttle control circuit
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.
• Inspect the throttle body for dirt or obstructions
• Check the throttle position sensor for proper operation
• Test the electrical connections and wiring to the throttle control system
• Clean the throttle body
• Replace the throttle position sensor if faulty
• Repair or replace any damaged wiring or connectors
• OBD-II scanner
• Multimeter
• Throttle body cleaner
$100 - $300
Moderate
• Ford Focus
• Chevrolet Silverado
• Toyota Camry
• Regularly clean the throttle body
• Ensure proper maintenance of the air intake system
• Check electrical connections periodically
Engine Performance
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
• Consult with a professional mechanic for accurate diagnosis and repair.
Check your vehicle's warranty for coverage on throttle control components.
P1638 has been reported in various models, often related to throttle body issues due to wear or contamination.
Moderate – Addressing this issue can prevent further engine performance problems.
Driving with a malfunctioning throttle can lead to unsafe driving conditions. Address the issue promptly.
• Engine running
• Vehicle at operating temperature
The throttle body is typically located between the air intake and the intake manifold.
Q: Can I drive with a P1638 code?
A: It's not recommended, as it may cause engine performance issues and unsafe driving conditions.
Q: How often should the throttle body be cleaned?
A: It's advisable to clean the throttle body every 30,000 to 50,000 miles, depending on driving conditions.
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