OBD-II code · Powertrain (manufacturer / generic)
P3402 Cylinder 1 Deactivation Performance/Stuck Off
The engine control module has detected that cylinder 1 remains deactivated when activation is commanded — the cylinder does not contribute to combustion when expected.
Is it safe to drive with P3402?
Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.
Common causes
- Most likelyLifter stuck collapsed
- PossibleSolenoid stuck
- Less likelyCarbon or debris buildup preventing free movement
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 2–10 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Cylinder Deactivation Solenoid, Lifter, Oil Control Valve
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.