OBD-II code · Powertrain (manufacturer / generic)
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.
Is it safe to drive with P3494?
Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.
Common causes
- Most likelySensor drift or aging
- PossibleLifter mechanical drag
- Less likelySensor face contamination
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1.5–7 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Position Sensor, Lifter
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.