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 learning where the throttle should stop when it's closed. It's like when you try to close a door, but it doesn't know where the floor is.
The engine control module (ECM) is unable to correctly learn the lower mechanical stop of the throttle valve during adaptation.
The P1644 code indicates that the ECM has detected an issue with the throttle valve adaptation process, specifically with the lower mechanical stop on Bank 1. This can occur if the throttle valve is not properly calibrated or if there is an obstruction preventing it from reaching its intended position.
• Check Engine Light is on
• Poor engine performance
• Erratic idling
• Faulty throttle body
• Dirty or clogged throttle valve
• Faulty throttle position sensor
Throttle Body: A component of the air intake system that controls the amount of air entering the engine.
ECM: Engine Control Module, the computer that controls engine functions.
• Check for any additional codes and address them first.
• Inspect the throttle body for dirt or obstructions.
• Perform a throttle body adaptation procedure using a scan tool.
• Clean the throttle body.
• Replace the throttle position sensor if faulty.
• Perform a throttle adaptation reset with a scan tool.
• OBD-II scan tool
• Throttle body cleaner
• Basic hand tools
$100 - $300
Moderate
• Volkswagen Golf
• Audi A4
• BMW 3 Series
• Regularly clean the throttle body.
• Ensure proper maintenance of the throttle system.
• Use quality fuel to prevent deposits.
Engine Performance
• Do not ignore the Check Engine Light.
• Have the vehicle checked by a professional if unsure.
• Perform regular maintenance to prevent future issues.
Check with your vehicle's manufacturer for specific warranty coverage on the throttle system.
This code has been more common in vehicles with electronic throttle control systems introduced in the early 2000s.
Moderate – It should be addressed soon to prevent further engine performance issues.
Driving with a malfunctioning throttle system can lead to unsafe driving conditions.
• Engine at operating temperature
• Throttle valve adaptation procedure initiated
The throttle body is typically located between the air filter and the intake manifold.
Q: What does the throttle valve do?
A: The throttle valve controls the amount of air entering the engine, which affects engine power and speed.
Q: Can I drive with a P1644 code?
A: It's not recommended, as it can lead to poor engine performance and potential safety issues.
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