P1128 Honda 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 Honda 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.
Code P1128 Honda Description
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.
What are the Possible Causes of the DTC P1128 Honda?
- 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 Honda?
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 Honda 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 Honda code?
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Need Help with the Code?
Get the P1128 Honda code diagnosed by a professional: Find a repair shop in your area
Information for Specific Honda Models
- P1128 2008 Honda Accord — Manifold Absolute Pressure Sensor Signal Lower Than Expected
- P1128 2009 Honda Accord — Manifold Absolute Pressure Sensor Signal Lower Than Expected
- P1128 2010 Honda Accord — Manifold Absolute Pressure Sensor Signal Lower Than Expected
- P1128 1996 Honda Civic — Manifold Absolute Pressure Sensor Signal Lower Than Expected
- P1128 1997 Honda Civic — Manifold Absolute Pressure Sensor Signal Lower Than Expected
- P1128 1998 Honda Civic — Manifold Absolute Pressure Sensor Signal Lower Than Expected
- P1128 1999 Honda Civic — Manifold Absolute Pressure Sensor Signal Lower Than Expected
- P1128 2000 Honda Civic — Manifold Absolute Pressure Sensor Signal Lower Than Expected
Frequently Asked Questions about P1128 Honda Code
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