P1129 Code - Downstream Oxygen Sensors Swapped from Bank to Bank
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 indicates Downstream Oxygen Sensors Swapped from Bank to Bank .
- 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.
Code P1129 Description
What are the Possible Causes of the DTC P1129?
- 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?
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 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.
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Information for Specific Makes
- P1129 Acura — Manifold Absolute Pressure Sensor Circuit Higher Than Expected
- P1129 Audi — Long Term Fuel Trim B2 System Too Rich
- P1129 Chrysler — Closed Loop Fueling Not Achieved Bank 2
- P1129 Dodge — Closed Loop Fueling Not Achieved Bank 2
- P1129 Ford — Downstream Oxygen Sensors Swapped from Bank to Bank
- P1129 Honda — Manifold Absolute Pressure Sensor Circuit Higher Than Expected
- P1129 Jeep — Closed Loop Fueling Not Achieved Bank 2
- P1129 Land Rover — HO2S Swapped Sensors Left Side To Right Side
- P1129 Lexus — Electric Throttle Control System Malfunction
- P1129 Lincoln — Downstream Oxygen Sensors Swapped from Bank to Bank
- P1129 Mercury — Downstream Oxygen Sensors Swapped from Bank to Bank
- P1129 Mitsubishi — Closed Loop Fueling Not Achieved Bank 2
- P1129 Toyota — Electric Throttle Control System Malfunction
- P1129 Volkswagen — Long Term Fuel Trim B2 System Too Rich
Frequently Asked Questions about P1129 Code
1. What are the common symptoms of OBDII code P1129 related to downstream oxygen sensors swapped from bank to bank?
- Common symptoms include poor fuel economy, rough idling, engine misfires, and possibly a check engine light illuminated on the dashboard.
2. What could cause downstream oxygen sensors to be swapped from bank to bank triggering code P1129?
- The most common cause is a wiring issue, where the sensor signals are crossed or incorrectly connected during installation or repair.
3. How serious is OBDII code P1129 and should it be addressed immediately?
- While the vehicle may still be drivable with this code, it is important to address it promptly to prevent potential damage to the catalytic converter and ensure optimal engine performance.
4. Can I continue driving my vehicle with OBDII code P1129 until I can get it fixed?
- It is generally not recommended to drive the vehicle for an extended period with this code present, as it can lead to decreased fuel efficiency and potential long-term damage to the engine components.
5. What is the typical repair process for resolving OBDII code P1129 related to downstream oxygen sensors swapped from bank to bank?
- The repair usually involves identifying the swapped sensors, correcting the wiring connections, and clearing the error code using an OBDII scanner.
6. How can I prevent downstream oxygen sensors from being swapped from bank to bank in the future?
- To prevent this issue, always double-check the sensor connections when replacing them and follow the manufacturer's guidelines for sensor installation.
7. Are there any DIY tips for troubleshooting OBDII code P1129 before taking the vehicle to a professional mechanic?
- You can visually inspect the sensor connections, check for any visible wiring issues, and ensure that the correct sensors are installed in their designated locations.
8. Will resetting the error code using an OBDII scanner fix the issue permanently?
- Simply clearing the error code may temporarily turn off the check engine light, but if the underlying wiring issue causing the sensors to be swapped is not fixed, the code is likely to reappear.
9. Is it possible for a faulty downstream oxygen sensor to trigger code P1129 even if the sensors are not physically swapped?
- Yes, a malfunctioning downstream oxygen sensor can sometimes send incorrect signals that mimic the effects of swapped sensors, triggering code P1129.
10. How much should I expect to pay for professional repairs related to OBDII code P1129 due to downstream oxygen sensors swapped from bank to bank?
- The cost of repairs can vary depending on the extent of the wiring issue and the labor rates of the mechanic, but it is generally a relatively straightforward and affordable fix compared to other engine problems.
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