The OBD code P1129 for Dodge indicates an issue with the fuel delivery system, Engine Coolant Temperature (ECT) sensor or wiring connectors, MAP sensor or wiring connectors, O2 sensor wiring or connectors, or engine mechanical system.
Symptoms include the Engine Light being ON.
To fix, inspect the mentioned components for damage or corrosion and ensure connectors are in good condition.
This issue should be addressed promptly to prevent further damage.
Repair Importance Level | 10.0 (Out of 10) |
Estimated Repair Time | Approximately 1.0 hour |
Repair Difficulty Level | 10.0 (Out of 10) |
Symptoms of the Dodge p1129 OBD Code
The Dodge P1129 fault code may indicate issues with the downstream oxygen sensor.
- Symptoms: Engine Light ON.
- Reduced engine power.
- Rough idle.
- Engine stalling.
- Hesitation during acceleration.
Causes of the Dodge p1129 OBD Code
Possible triggers for Dodge fault code P1129 include issues with the MAP sensor, vacuum leaks, or throttle body problems.
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- P1129 can be caused by a faulty fuel delivery system.
- A malfunctioning Engine Coolant Temperature (ECT) sensor or wiring connectors.
- A defective MAP sensor or wiring connectors.
- Faulty O2 sensor wiring or connectors.
- Issues within the engine mechanical system.
Fixing Dodge Error Code p1129 Step By Step
Address the issue by inspecting the throttle control system for potential faults or failures.
- To fix Dodge OBDII code P1129, start by reviewing the possible causes mentioned above.
- Visually examine the corresponding wiring harness and connectors for any damage.
- Check the connector pins for signs of being broken, bent, pushed out, or corroded.
- If no issues are found with the wiring, consider replacing the throttle control motor or the throttle position sensor as they are common culprits for this fault code.
- Clear the code after any repairs are made and test drive the vehicle to ensure the issue has been resolved.
Cost Of Fixing Dodge p1129 Fault Code
The repair for Dodge code P1129 may involve replacing the thermostat or addressing cooling system issues.
The cost to diagnose and fix the Dodge OBD code P1129 depends on the estimated 1. 0hour repair time.
Labor rates usually range from $75 to $150 per hour, so the cost can vary between $75 and $150, excluding parts.
Factors like shop rates and the complexity of the repair can influence the final cost.
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Details of the Dodge p1129 OBD Code
Dodge fault code P1129 relates to an issue with the downstream oxygen sensor.
Dodge OBD code P1129 means the Long Term Fuel Trim is too Rich (Bank 2).
It is triggered by the Engine Control Module (ECM) based on the oxygen sensor feedback indicating a consistently rich airfuel mixture on Bank 2 of the engine.
This code is related to the fuel delivery system and can be caused by issues such as a faulty oxygen sensor, fuel pressure regulator, or fuel injector on Bank 2.
Mechanic’s Tech Notes
Detailed information on Dodge fault code P1129, including symptoms, causes, and repair procedures.
OBDII code P1129 in a Dodge typically indicates an issue with the TCM (Transmission Control Module).
To diagnose, check TCM power and ground using a multimeter.
Verify TCM communication over the CAN network with a scan tool.
If the wiring harness or connectors show signs of damage, repair or replace as needed.
Reflashing the TCM may also be necessary to resolve the fault.
Be thorough in your visual inspection of components and connector pins for any issues like corrosion, bending, or breakage.
FAQ
OBD code P1129 in a Dodge may be caused by issues with fuel delivery system, ECT sensor, MAP sensor, O2 sensor wiring, or engine mechanical system. Check corresponding components and wiring.
Diagnose P1129 in Dodge: Check fuel system, ECT sensor, MAP sensor, O2 sensor, engine components. Inspect wiring for damage, corrosion, bent pins. Fix as needed.
Yes, it is generally safe to drive with OBD code P1129 in a Dodge. Check fuel delivery system, ECT sensor, MAP sensor, O2 sensor, and engine components for issues.

Wrap Up
If your Dodge is displaying OBD code P1129 along with poor engine performance and reduced fuel efficiency, it may indicate a fault in the downstream oxygen sensor circuit.
Possible causes include a faulty downstream oxygen sensor, damaged wiring, or a poor electrical connection.
To address Dodge OBD code P1129, start by inspecting the downstream oxygen sensor and its wiring harness for any signs of damage or corrosion.
Test the sensor’s electrical connector for proper connection and continuity.
If necessary, replace the downstream oxygen sensor and repair any wiring issues to resolve the fault.
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