Powertrain
generic / SAE
P0174
System Too Lean (Bank 2)
Same condition as P0171 but on bank 2 of a multi-bank engine (V6, V8, flat-six, etc.). When P0171 and P0174 appear together, the cause is usually a shared component such as the MAF sensor or a central vacuum leak rather than a bank-specific fault.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number1 / 74
Possible causes
- Central vacuum leak (intake manifold gasket, brake booster) high
- MAF sensor contaminated high
- Fuel pressure low (affects both banks) medium
Symptoms
- Check engine light on
- Rough idle, possible stalling
- Hesitation or hard cold start
- Power loss under load
Inspection / repair
- Difficulty: medium
- DIY: possible
- Estimated cost: 50–600 €
- Estimated time: 0.5–4 h
- Component: intake manifold
- Component: mass air flow sensor
- Component: fuel pump
- Component: fuel pressure regulator
- MIL / check engine light
- emissions-relevant
- drive cycle required
Sources
References
sae:J2012