Audi DTC P1139 – Long Term Fuel Trim Additional Fuel, Bank2 System too Rich
DTC P1139 meaning on Audi
The Diagnostic Trouble Code (DTC) P1139 for Audi indicates that the Long Term Fuel Trim Additional Fuel, Bank 2 system is reading as too rich. This means that the engine control module (ECM) has detected that the amount of fuel being added to the air-fuel mixture in Bank 2 is higher than necessary for proper combustion.
Audi DTC P1139 symptoms
Symptoms associated with DTC P1139 on an Audi may include:
- Decreased fuel efficiency
- Black smoke from the exhaust
- Rough idling or stalling
- Check Engine Light illuminated on the dashboard
Audi DTC P1139 causes
The potential causes of DTC P1139 on an Audi can include:
- Faulty oxygen sensor
- Vacuum leaks in the intake system
- Issues with the fuel injectors
- Malfunctioning mass airflow sensor
- Exhaust system leaks
Audi DTC P1139 seriousness
While DTC P1139 may not cause immediate drivability issues, it can lead to decreased fuel efficiency and potential long-term damage to the engine if left unresolved. It is important to address this issue promptly to prevent further complications.
How to diagnose DTC P1139 on Audi
To diagnose DTC P1139 on an Audi, a mechanic may perform the following steps:
- Use a diagnostic scanner to retrieve the fault codes
- Inspect the oxygen sensor readings
- Check for vacuum leaks in the intake system
- Test the fuel injectors and mass airflow sensor
- Inspect the exhaust system for leaks
How to fix DTC P1139 on Audi
To fix DTC P1139 on an Audi, the following steps may be taken:
- Replace the faulty oxygen sensor
- Repair any vacuum leaks in the intake system
- Clean or replace the fuel injectors
- Replace the malfunctioning mass airflow sensor
- Repair any leaks in the exhaust system
How to erase DTC P1139 on Audi
After addressing the underlying issue causing DTC P1139 on an Audi, the fault codes can be erased using a diagnostic scanner. This will reset the Check Engine Light and allow the ECM to monitor the system for any new faults.
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