P0174: System zu mager (Bank 2)
System zu mager (Bank 2): Excessive positive fuel trim correction on Bank 2 cylinder bank.
| Trouble Code (DTC) | P0174 |
|---|---|
| Official SAE Definition | System zu mager (Bank 2) |
| Vehicle Subsystem | powertrain |
| Driving Severity | MEDIUM |
Observable Symptoms
- Rough idle
- Hesitation under load
- MIL illuminated
Most Probable Root Causes
- Intake plenum or vacuum leak affecting Bank 2
- Contaminated MAF sensor
- Weak fuel pump or clogged Bank 2 injectors
Step-by-Step Diagnostic Procedure
- Compare Bank 1 and Bank 2 LTFT values at idle and 2,500 RPM
- Inspect intake boots and PCV breather lines
- Measure fuel rail pressure under load