P34A3
Cylinder 12 Deactivation/Intake Valve Performance
Per-cylinder intake valve deactivation on cylinder 12 does not respond as commanded.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: hard
Common causes
Ordered by how often each turns out to be the cause.
- Actuator stuck mechanicallyCommon
Parts involved
- Cyl12 Intake Valve Actuator
- Hydraulic Pin
P34A3 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.