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 valve stops when it closes. 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 properly adapt or learn the lower mechanical stop position of the throttle valve for Bank 2.
The throttle valve is a component that controls the amount of air entering the engine. The ECM needs to know the exact position of the throttle valve to ensure proper engine performance and efficiency. When the ECM cannot determine the lower mechanical stop position of the throttle valve on Bank 2, it triggers this error code. This can affect engine idling and performance.
• Check Engine Light is on
• Poor engine performance
• Unstable idling
• Faulty throttle body
• Wiring issues or poor connections
• Faulty ECM
Throttle Valve: A component that controls the amount of air entering the engine.
ECM: Engine Control Module, the computer that manages engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the throttle body for damage or obstructions.
• Check wiring and connections related to the throttle body.
• Clean or replace the throttle body.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Throttle body cleaner
$200 - $600
Moderate
• Audi A6
• Volkswagen Passat
• Porsche Cayenne
• Regularly clean the throttle body.
• Ensure proper maintenance of electrical connections.
• Perform routine engine diagnostics.
Engine Performance
• Have the vehicle inspected by a professional mechanic.
• Avoid driving the vehicle aggressively until the issue is resolved.
Check with your vehicle manufacturer for warranty coverage on engine control components.
This code has been more common in vehicles with electronic throttle control systems, particularly in models with higher mileage.
Moderate – Should be addressed soon to prevent further engine performance issues.
Ignoring this code may lead to increased emissions and reduced fuel efficiency.
• Engine at operating temperature
• Throttle valve in closed position
The throttle body is located between the air filter and the intake manifold, typically near the front of the engine bay.
Q: Can I drive with a P16AF code?
A: It's not recommended to drive for long periods with this code as it may affect engine performance.
Q: How do I reset the throttle adaptation?
A: A mechanic can reset the throttle adaptation using a diagnostic tool.
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