AutoCodes – Honda – P1129 2009 Honda Accord

P1129 2009 Honda Accord Code - Manifold Absolute Pressure Sensor Circuit Higher Than Expected

Quick Answer

The Manifold Αbsolute Pressure (MΑP) sensor generates a signal that is proportional to the amount of vacuum in the intake manifold. Common causes include Faulty Manifold Absolute Pressure Sensor, Manifold Absolute Pressure Sensor harness is open or shorted, Manifold Absolute Pressure Sensor circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P1129 2009 Honda Accord indicates Manifold Absolute Pressure Sensor Circuit Higher Than Expected.
Common causes: Common causes include Faulty Manifold Absolute Pressure Sensor, Manifold Absolute Pressure Sensor harness is open or shorted, Manifold Absolute Pressure Sensor circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 5,159

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Apr 27, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1129 2009 Honda Accord Description

The Manifold Αbsolute Pressure (MΑP) sensor generates a signal that is proportional to the amount of vacuum in the intake manifold. The signal is sent to the Engine Control Mudule (ECM) and the information is used to control the air/fuel mixture ratio. Faulty MΑP sensor can cuase the engine to stall, surge or a rough idle.

OBDII Code P1129 2009 Honda Accord - Manifold Absolute Pressure Sensor Circuit Higher Than Expected - AutoCodes.com — P1129 2009 Honda Accord Code - Manifold Absolute Pressure Sensor Circuit Higher Than Expected

What does this mean?

What are the Possible Causes of the DTC P1129 2009 Honda Accord?

Faulty Manifold Absolute Pressure Sensor
Manifold Absolute Pressure Sensor harness is open or shorted
Manifold Absolute Pressure Sensor circuit poor electrical connection

How to Fix the DTC P1129 2009 Honda Accord?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1129 2009 Honda Accord code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P1129 2009 Honda Accord code?

Need more information on how to fix the P1129 2009 Honda Accord code? Get Access to Factory Service Manuals

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P1129 2009 Honda Accord Code

1. What are the common symptoms of OBDII code P1129 on a 2009 Honda Accord?

- Common symptoms include poor engine performance, rough idling, stalling, and potentially reduced fuel efficiency.

2. What does the OBDII code P1129 on a 2009 Honda Accord indicate?

- This code indicates that the Manifold Absolute Pressure (MAP) sensor circuit is detecting a higher than expected pressure.

3. What are some possible causes of OBDII code P1129 on a 2009 Honda Accord?

- Possible causes include a faulty MAP sensor, a vacuum leak, a clogged or dirty air filter, or issues with the wiring or connections in the sensor circuit.

4. How can I diagnose the OBDII code P1129 on my 2009 Honda Accord?

- Diagnosis typically involves using a scan tool to read the code and then performing a visual inspection of the MAP sensor, checking for vacuum leaks, and testing the sensor's electrical connections.

5. Can I continue driving my 2009 Honda Accord with OBDII code P1129?

- It's not recommended to continue driving with this code as it can lead to further engine damage and potentially unsafe driving conditions.

6. How can I repair OBDII code P1129 on a 2009 Honda Accord?

- Repair options may include replacing the MAP sensor, fixing any vacuum leaks, cleaning or replacing the air filter, or addressing any wiring issues in the sensor circuit.

7. Is it possible to reset the OBDII code P1129 on a 2009 Honda Accord without fixing the underlying issue?

- While you can clear the code with a scan tool, it will likely reappear if the root cause is not addressed.

8. How much does it typically cost to repair OBDII code P1129 on a 2009 Honda Accord?

- The cost can vary depending on the specific issue, but it may range from $100 to $300 for parts and labor.

9. Can a DIY enthusiast fix OBDII code P1129 on a 2009 Honda Accord?

- Depending on the root cause and the individual's skill level, some DIY enthusiasts may be able to tackle the repair themselves, especially if it involves simple tasks like replacing the air filter or cleaning sensor connections.

10. Will OBDII code P1129 cause my 2009 Honda Accord to fail an emissions test?

- Yes, this code can cause your vehicle to fail an emissions test, so it's important to address the issue promptly to ensure your vehicle meets regulatory standards.