Volkswagen DTC P1138 – Long Term Fuel Trim Additional Fuel B2 System Too Lean
DTC P1138 meaning on Volkswagen
The Diagnostic Trouble Code (DTC) P1138 for Volkswagen indicates that the Long Term Fuel Trim Additional Fuel Bank 2 System is too lean. This means that the engine control module (ECM) has detected a lean condition in the fuel mixture for the bank 2 of the engine, which can lead to drivability issues and potential damage if not addressed promptly.
Volkswagen DTC P1138 symptoms
Symptoms associated with DTC P1138 on a Volkswagen may include:
- Check Engine Light (CEL) illuminated on the dashboard
- Decreased fuel efficiency
- Engine hesitation or misfiring
- Rough idling or stalling
- Lack of power during acceleration
Volkswagen DTC P1138 causes
The potential causes of DTC P1138 on a Volkswagen can include:
- Vacuum leaks in the intake system
- Faulty oxygen sensor (Bank 2 Sensor 1)
- Fuel delivery issues
- Dirty or clogged fuel injectors
- Exhaust leaks
Volkswagen DTC P1138 seriousness
While DTC P1138 may not always result in immediate drivability issues, it is important to address this code promptly to prevent potential damage to the engine and ensure optimal performance and fuel efficiency of the vehicle.
How to diagnose DTC P1138 on Volkswagen
To diagnose DTC P1138 on a Volkswagen, a mechanic would typically perform the following steps:
- Use a diagnostic scanner to retrieve the fault codes and freeze frame data
- Inspect the intake system for vacuum leaks
- Check the operation of the oxygen sensor (Bank 2 Sensor 1)
- Test the fuel delivery system for proper pressure and flow
- Clean or replace fuel injectors if necessary
- Inspect the exhaust system for leaks
How to fix DTC P1138 on Volkswagen
To fix DTC P1138 on a Volkswagen, the following steps may be taken:
- Repair any vacuum leaks in the intake system
- Replace the faulty oxygen sensor (Bank 2 Sensor 1)
- Address any fuel delivery issues
- Clean or replace clogged fuel injectors
- Repair any exhaust leaks
How to erase DTC P1138 on Volkswagen
Once the underlying issue causing DTC P1138 on a Volkswagen has been resolved, the fault codes can be cleared using a diagnostic scanner. This will reset the Check Engine Light and allow the vehicle’s ECM to monitor the system for any new faults.
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