AutoCodes – Generic – P1139

P1139 Code - Long Term Fuel Trim Add. Fuel B2 System Too Rich

Quick Answer

P1139 indicates Long Term Fuel Trim Add. Fuel B2 System Too Rich. Common causes include Faulty O2 Sensor, High fuel pressure, Faulty Mass Air Flow (MAF) Sensor. 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: P1139 indicates Long Term Fuel Trim Add. Fuel B2 System Too Rich.
Common causes: Common causes include Faulty O2 Sensor, High fuel pressure, Faulty Mass Air Flow (MAF) Sensor.
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 23,547

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Apr 30, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1139 Description

OBDII Code P1139 - Long Term Fuel Trim Add. Fuel B2 System Too Rich - AutoCodes.com — P1139 Code - Long Term Fuel Trim Add. Fuel B2 System Too Rich

What does this mean?

What are the Possible Causes of the DTC P1139?

Faulty O2 Sensor
High fuel pressure
Faulty Mass Air Flow (MAF) Sensor
O2 Sensor harness is open or shorted
O2 Sensor circuit poor electrical connection

How to Fix the DTC P1139?

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 P1139 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 P1139 code?

Need more information on how to fix the P1139 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1139 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P1139 Audi — Long Term Fuel Trim Add. Fuel B2 System Too Rich
P1139 BMW — O2 Sensor Heater Circuit High Voltage Bank 1 Sensor 2
P1139 Buick — HO2S Insufficient Switching Bank 1 Sensor 2
P1139 Cadillac — HO2S Insufficient Switching Bank 1 Sensor 2
P1139 Chevrolet — HO2S Insufficient Switching Bank 1 Sensor 2
P1139 Ford — Water In Fuel Indicator Circuit Malfunction
P1139 GMC — HO2S Insufficient Switching Bank 1 Sensor 2
P1139 MINI — O2 Sensor Heater Circuit High Voltage Bank 1 Sensor 2
P1139 Subaru — Front Oxygen A/F Sensor #1 Heater Circuit Performance/Range Problem
P1139 Volkswagen — Long Term Fuel Trim Add. Fuel B2 System Too Rich

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 P1139 Code

1. What are the common symptoms of OBDII code P1139?

- Common symptoms include decreased fuel efficiency, rough idling, engine misfires, and a strong smell of fuel from the exhaust.

2. What are some possible causes of OBDII code P1139?

- Potential causes include a faulty oxygen sensor, vacuum leaks, fuel pressure regulator issues, clogged fuel injectors, or a malfunctioning mass airflow sensor.

3. How can I diagnose the cause of OBDII code P1139?

- Diagnosing the issue may involve checking the oxygen sensor readings, inspecting for vacuum leaks, testing fuel pressure, examining fuel injector performance, and verifying the mass airflow sensor function.

4. Is it safe to continue driving with OBDII code P1139?

- It is not recommended to drive with this code unresolved, as it can lead to poor engine performance and potential damage to the catalytic converter over time.

5. Can I repair OBDII code P1139 myself?

- Depending on your mechanical skills and tools available, repairs for this code may range from simple tasks like replacing an oxygen sensor to more complex procedures involving fuel system diagnostics.

6. How much does it typically cost to fix OBDII code P1139?

- The cost of repairs for this code can vary widely depending on the specific cause, parts needed, and labor rates, but it may range from a few hundred to over a thousand dollars.

7. Will resetting the OBDII code P1139 resolve the issue?

- Simply resetting the code will not fix the underlying problem causing P1139. It is crucial to diagnose and address the root cause to prevent the code from reappearing.

8. Can a dirty air filter trigger OBDII code P1139?

- A dirty air filter can impact the air-fuel mixture but is unlikely to directly trigger P1139. However, maintaining a clean air filter is essential for overall engine performance.

9. How important is it to address OBDII code P1139 promptly?

- It is crucial to address this code promptly to ensure optimal engine performance, fuel efficiency, and emissions compliance while preventing potential damage to engine components.

10. Is it necessary to have a professional mechanic clear OBDII code P1139 after repairs?

- While not necessary, having a professional mechanic clear the code after repairs can ensure that the issue has been correctly addressed and verify that the code does not reappear.