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 turbo boost sensor is giving a reading that doesn't make sense after the car is turned off.
The engine control module (ECM) has detected that the pressure reading from the turbo boost sensor 'A' is not plausible during the afterrunning diagnostic phase.
The P129A code indicates that the ECM has found an implausible pressure reading from Boost Sensor 'A' during the afterrunning diagnostic process. This could be due to a faulty sensor, wiring issues, or a problem with the turbo system itself.
• Check engine light is on
• Reduced engine performance
• Poor fuel efficiency
• Faulty boost sensor
• Wiring issues or poor connections
• Turbocharger malfunction
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the boost sensor and its wiring for damage.
• Test the boost sensor with a multimeter.
• Replace the faulty boost sensor.
• Repair or replace damaged wiring or connectors.
• Inspect and repair the turbocharger if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Volkswagen Golf
• Audi A4
• Skoda Octavia
• Regularly inspect and maintain the turbo system.
• Ensure sensors and wiring are in good condition.
• Use high-quality fuel to prevent deposits.
Sensor Issue
• Have the vehicle inspected by a professional mechanic.
• Avoid driving at high speeds until the issue is resolved.
Check with your vehicle manufacturer for warranty coverage on sensors.
This code has been associated with turbocharged vehicles and is often due to sensor or wiring issues.
Moderate – It should be addressed soon to avoid potential engine performance issues.
Driving with this code active may lead to reduced engine performance and efficiency. It is advisable to have it checked promptly.
• Engine off
• Afterrunning diagnostic phase active
The boost sensor is typically located near the intake manifold or turbocharger.
Q: Can I drive with a P129A code?
A: It's not recommended to drive for long periods with this code active, as it can lead to reduced performance.
Q: How do I clear a P129A code?
A: You can clear the code with an OBD-II scanner after fixing the underlying issue.
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