AutoCodes – Honda – P1129 1998 Honda Civic

P1129 1998 Honda Civic 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 1998 Honda Civic 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 3,876

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 1998 Honda Civic 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 1998 Honda Civic - Manifold Absolute Pressure Sensor Circuit Higher Than Expected - AutoCodes.com — P1129 1998 Honda Civic Code - Manifold Absolute Pressure Sensor Circuit Higher Than Expected

What does this mean?

What are the Possible Causes of the DTC P1129 1998 Honda Civic?

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 1998 Honda Civic?

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 1998 Honda Civic 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 1998 Honda Civic code?

Need more information on how to fix the P1129 1998 Honda Civic 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 1998 Honda Civic Code

1. What are the common symptoms of OBDII code P1129 in a 1998 Honda Civic?

- Common symptoms include reduced engine performance, rough idling, stalling, and possible hesitation during acceleration.

2. What does the OBDII code P1129 in a 1998 Honda Civic mean?

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

3. What are the possible causes of OBDII code P1129 in a 1998 Honda Civic?

- Possible causes include a faulty MAP sensor, a vacuum leak in the intake system, a clogged air filter, or wiring/connectivity issues in the sensor circuit.

4. How can I diagnose the OBDII code P1129 in my 1998 Honda Civic?

- You can diagnose the code by visually inspecting the MAP sensor and its wiring, checking for vacuum leaks, testing the sensor's voltage output, and using a scan tool to monitor sensor data.

5. Can I still drive my 1998 Honda Civic with OBDII code P1129?

- It is not recommended to drive the vehicle with this code active, as it can lead to poor engine performance and potential damage if left unresolved.

6. How can I repair OBDII code P1129 in my 1998 Honda Civic?

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

7. Will resetting the OBDII code P1129 in my 1998 Honda Civic make it go away?

- Resetting the code may temporarily turn off the check engine light, but if the underlying issue is not fixed, the code is likely to return after driving the vehicle.

8. Is it safe to ignore OBDII code P1129 in my 1998 Honda Civic?

- Ignoring the code can lead to decreased fuel efficiency, engine performance issues, and potential damage to other engine components, so it's best to address it promptly.

9. Can a DIY enthusiast fix OBDII code P1129 in a 1998 Honda Civic?

- Depending on your skill level and available tools, you may be able to fix the issue yourself by following repair guides and tutorials specific to your vehicle.

10. How much does it cost to repair OBDII code P1129 in a 1998 Honda Civic at a professional mechanic?

- The cost of repair can vary based on the root cause of the issue, but it typically ranges from $100 to $300 for parts and labor at a professional mechanic's shop.