Long term fuel trim, idling, Bank 2 - system too lean
VAG · fuel
Data confidence62%
The control module detected that the air-fuel mixture stayed leaner than the target despite full corrective control (Long term fuel trim, idling, Bank 2 - system). This is the manufacturer-specific definition used by Audi.
Possible causes
Fuel pressure/pump
injector(s)
intake/ exhaust leak
AIR system
hose leak
Applies toAudi
P1138
Long term fuel trim, idling, system too lean
VAG · fuel
Data confidence80%
The control module detected that the air-fuel mixture stayed leaner than the target despite full corrective control (Long term fuel trim, idling, system). This is the manufacturer-specific definition used by Volkswagen.
Powertrain: engine, transmission and driveline systems.
1
Manufacturer-defined range: the meaning can differ between brands.
138
Specific fault index within the subsystem.
Frequently asked questions about P1138
What does P1138 mean?
Diagnostic Trouble Code (2 interpretations). The control module detected that the air-fuel mixture stayed leaner than the target despite full corrective control (Long term fuel trim, idling, Bank 2 - system). This is the manufacturer-specific definition used by Audi.
Is P1138 generic or manufacturer-specific?
P1138 is a manufacturer-specific code. In this database it is documented for: VAG. The same number can mean something different on other brands.
Can TuningBot remove P1138 at file level?
If the fault logic lives in the ECU calibration, yes: our DTC Removal file service disables the specific fault entry. Checksum correction is not included: it is a separate, optional service. Not sure whether your case qualifies? Request a free assessment and our engineers will check your ECU file.