Audi DTC P1138 – Long Term Fuel Trim Additional Fuel, Bank2 System too Lean
DTC P1138 meaning on Audi
DTC P1138 on an Audi indicates that the Long Term Fuel Trim Additional Fuel, Bank 2 system is running too lean. This means that the engine control module (ECM) has detected that the amount of fuel being added to the mixture in Bank 2 is not enough to maintain the proper air-fuel ratio.
Audi DTC P1138 symptoms
Symptoms of DTC P1138 on an Audi may include rough idling, poor acceleration, decreased fuel efficiency, engine misfires, and potentially the illumination of the check engine light on the dashboard.
Audi DTC P1138 causes
The causes of DTC P1138 on an Audi can vary, but common culprits include a vacuum leak, faulty oxygen sensor, clogged fuel injectors, fuel pump issues, intake air leaks, or a problem with the mass airflow sensor.
Audi DTC P1138 seriousness
While DTC P1138 may not cause immediate harm to the engine, it can lead to poor performance and decreased fuel efficiency. Ignoring this issue can potentially cause damage to other components of the vehicle over time.
How to diagnose DTC P1138 on Audi
To diagnose DTC P1138 on an Audi, a mechanic would typically use a diagnostic scanner to retrieve the trouble codes and then perform a thorough inspection of the fuel system, oxygen sensors, air intake system, and other related components to identify the root cause of the lean condition.
How to fix DTC P1138 on Audi
Fixing DTC P1138 on an Audi may involve replacing a faulty oxygen sensor, repairing vacuum leaks, cleaning or replacing clogged fuel injectors, addressing fuel pump issues, or fixing any other component that is contributing to the lean condition in Bank 2.
How to erase DTC P1138 on Audi
Once the underlying issue causing DTC P1138 on an Audi has been resolved, the trouble codes can be cleared using a diagnostic scanner. This will reset the check engine light and allow the vehicle to monitor the system for any new issues.
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