P2179System Too Lean Off Idle (Bank 2)
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- P2179 is the bank 2 version of P2177 on engines with a front oxygen sensor for each cylinder bank: the load-dependent, multiplicative share of bank 2's long-term correction has reached its lean limit. GM's 2005 2.8 and 3.6 V6 and the 2008 3.6 LLT use a factor above 1.23, GM's 2024 tables above 1.27, both over two trips. VW's 2014 Touareg sets it for the 3.0 TSI hybrid and the 3.6 VR6 when bank 2 adaptation exceeds +30 %. If both banks are lean at load, look at what they share: fuel pressure, the pump, the air mass sensor. If bank 2 alone is affected, the cause lies on that side, such as a restricted injector, an intake leak at that bank's manifold or a front sensor reading lean. No bulletin naming this code was found.
- What you may notice
- Check engine lamp on after two trips
- Hesitation under load
- Likely causes
- PossibleLow fuel pressure or air mass sensor fault, usually with P2177 too
- PossibleRestricted injector on bank 2
- PossibleIntake leak or front oxygen sensor fault on bank 2
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €0 – €800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.