P0171
System Too Lean (Bank 1)
System: Air/Fuel
Severity: medium
What does P0171 mean?
The DTC P0171 (System Too Lean (Bank 1)) is a fault code stored by the ECU when it detects a lean condition condition in the air/fuel subsystem. It is commonly seen on European and Asian vehicles using Bosch, Continental, Siemens or Denso ECUs.
Common causes of P0171
- Vacuum leak
- Failed fuel pump/regulator
- Dirty MAF
- Clogged injectors
How to fix P0171
Smoke test for vacuum leaks first. DaVinci can fine-tune fuel trims after mechanical fix.
Tuning approach with DaVinci Deluxe · Cloud Edition
For P0171, DaVinci Deluxe · Cloud Edition offers the following ECU map adjustments and software solutions:
- Long-term fuel trim adjust
- Injector flow scaling
- Lambda target tweak
Need to fix P0171 on your ECU?
DaVinci Deluxe · Cloud Edition is professional ECU tuning software trusted by 800+ workshops. 24-Hour Pass €45.99, 10 minutes free trial.
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