Powertrain
generic / SAE
P2189
System Too Lean at Idle (Bank 2)
Fuel trim on bank 2 hits the lean limit only at idle, while trim returns to normal at higher load. This pattern strongly indicates a vacuum leak — leaks become a larger fraction of total airflow at idle and so dominate the trim, but disappear into background noise above idle.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number1 / 89
Possible causes
- Vacuum leak on bank 2 high
- PCV valve stuck open 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: 20–600 €
- Estimated time: 0.3–4 h
- Component: intake manifold
- Component: pcv valve
- Component: vacuum hose
- MIL / check engine light
- emissions-relevant
- drive cycle required
Sources
References
sae:J2012