P3494
Cylinder Deactivation Position Sensor Bank 1 Range/Performance
The engine control module has detected the bank 1 cylinder deactivation position sensor signal is within electrical limits but does not change as expected during commanded deactivation transitions. Mechanical drag, sensor drift or contamination is the typical cause.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: hard
Common causes
Ordered by how often each turns out to be the cause.
- Sensor drift or agingCommon
- Lifter mechanical dragPossible
- Sensor face contaminationLess likely
Parts involved
- Position Sensor
- Lifter
P3494 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.