P1129 – Honda DTC

Honda DTC P1129 – MAP Higher Than Expected

DTC P1129 meaning on Honda

1. DTC P1129 stands for Manifold Absolute Pressure (MAP) Sensor Higher Than Expected for Honda vehicles.
2. This diagnostic trouble code indicates that the MAP sensor is detecting a higher than expected pressure in the intake manifold.

Honda DTC P1129 symptoms

• Check Engine Light (CEL) illuminated on the dashboard.
• Reduced engine performance or power.
• Possible engine stalling or rough idling.

Honda DTC P1129 causes

• Faulty MAP sensor.
• Vacuum leaks in the intake system.
• Issues with the intake manifold gasket.
• Problems with the wiring or connectors related to the MAP sensor.

Honda DTC P1129 seriousness

1. If left unresolved, DTC P1129 can lead to poor engine performance and potential damage to other engine components.
2. It is recommended to address this issue promptly to prevent further complications.

How to diagnose DTC P1129 on Honda

1. Use an OBD-II scanner to retrieve the specific trouble code and related data.
2. Inspect the MAP sensor and its wiring for any visible damage or loose connections.
3. Check for vacuum leaks in the intake system using a smoke machine or other diagnostic tools.

How to fix DTC P1129 on Honda

1. Replace the faulty MAP sensor if it is determined to be the cause of the issue.
2. Repair any vacuum leaks in the intake system and replace the intake manifold gasket if necessary.
3. Ensure all wiring and connectors related to the MAP sensor are in good condition.

How to erase DTC P1129 on Honda

1. After addressing the root cause of the issue, use an OBD-II scanner to clear the trouble code from the vehicle’s memory.
2. Ensure that the issue has been resolved before clearing the code to prevent it from reoccurring.

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