P2E68
System Too Lean During Cylinder Deactivation Bank 1
During cylinder deactivation on bank 1, the fuel trim of the active cylinders runs persistently lean. Indicates unmetered air ingress or fuel delivery shortfall.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Symptoms
- Check engine light on
- Rough idle, possible stalling
- Hesitation or hard cold start
- Power loss under load
Common causes
Ordered by how often each turns out to be the cause.
- Vacuum leak unmasked during deactivationCommon
- Fuel rail pressure lowPossible
Parts involved
- Fuel Injectors
- Deactivation Solenoids
- Intake System
P2E68 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.