AutoCodes – Honda – P1128 2000 Honda Civic

P1128 2000 Honda Civic Code - Manifold Absolute Pressure Sensor Signal Lower Than Expected

Quick Answer

The Manifold Absolute Pressure (MAP) sensor senses manifold absolute pressure (vacuum) and converts it into electrical signals. Common causes include Engine mechanical condition, Faulty Manifold Absolute Pressure (MAP) sensor, Manifold Absolute Pressure (MAP) sensor harness is open or shorted. 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: P1128 2000 Honda Civic indicates Manifold Absolute Pressure Sensor Signal Lower Than Expected.
Common causes: Common causes include Engine mechanical condition, Faulty Manifold Absolute Pressure (MAP) sensor, Manifold Absolute Pressure (MAP) sensor harness is open or shorted.
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 4,056

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 26, 2019

Description
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1128 2000 Honda Civic Description

The Manifold Absolute Pressure (MAP) sensor senses manifold absolute pressure (vacuum) and converts it into electrical signals. The MAP sensor outputs low signal voltage at high-vacuum (idling) and high signal voltage at low-vacuum (throttle valve wide open).
The Engine Control Module (ECM) compares a predetermined MAP value at a given throttle position and manifold absolute pressure to the output voltage value of the MAP sensor.
If the MAP sensor outputs lower voltage than expected, the ECM detects a malfunction and stores a DTC.

OBDII Code P1128 2000 Honda Civic - Manifold Absolute Pressure Sensor Signal Lower Than Expected - AutoCodes.com — P1128 2000 Honda Civic Code - Manifold Absolute Pressure Sensor Signal Lower Than Expected

What does this mean?

What are the Possible Causes of the DTC P1128 2000 Honda Civic?

Engine mechanical condition
Faulty Manifold Absolute Pressure (MAP) sensor
Manifold Absolute Pressure (MAP) sensor harness is open or shorted
Manifold Absolute Pressure (MAP) sensor circuit poor electrical connection

How to Fix the DTC P1128 2000 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 P1128 2000 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 P1128 2000 Honda Civic code?

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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 P1128 2000 Honda Civic Code

1. What are the common symptoms of OBDII code P1128 in a 2000 Honda Civic?

- Common symptoms include loss of power, poor fuel efficiency, rough idle, and potentially stalling.

2. What does the OBDII code P1128 on a 2000 Honda Civic indicate?

- The code P1128 indicates that the Manifold Absolute Pressure (MAP) sensor signal is lower than expected.

3. What are the possible causes of OBDII code P1128 in a 2000 Honda Civic?

- Possible causes include a faulty MAP sensor, vacuum leaks, intake manifold issues, or wiring/connectivity problems.

4. How can I diagnose the cause of OBDII code P1128 in my 2000 Honda Civic?

- You can use a diagnostic scanner to read the code, check the MAP sensor readings, inspect for vacuum leaks, and test the sensor's wiring.

5. Can I drive my 2000 Honda Civic with OBDII code P1128?

- It is not recommended to drive your vehicle with this code as it can lead to performance issues and potential damage to the engine.

6. How can I repair OBDII code P1128 on my 2000 Honda Civic?

- Repair options include replacing the MAP sensor, fixing any vacuum leaks, addressing intake manifold issues, or repairing wiring/connectivity problems.

7. Is it possible to reset OBDII code P1128 on a 2000 Honda Civic without fixing the issue?

- While you can clear the code temporarily, it will likely reappear if the underlying problem is not resolved.

8. Will fixing OBDII code P1128 improve the performance and fuel efficiency of my 2000 Honda Civic?

- Yes, addressing the issue causing the code can help restore your vehicle's performance and fuel efficiency.

9. How much does it cost to repair OBDII code P1128 on a 2000 Honda Civic?

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

10. Can a DIY enthusiast fix OBDII code P1128 on a 2000 Honda Civic?

- Depending on your skill level and access to tools, you may be able to replace the MAP sensor or address vacuum leaks yourself. However, more complex issues may require professional help.