Code result
P3407
Cylinder 1 Deactivation Stuck On
Moderate severity
What it means
The engine control module has detected that cylinder 1 deactivation hardware is stuck in the active state. Cylinder 1 stays deactivated when full-cylinder operation is commanded.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Solenoid stuck in deactivation position
highOne of the most commonly reported causes for this code — check this first.
Lifter stuck collapsed
mediumA plausible cause — test and verify before replacing parts.
Carbon or debris buildup preventing free movement
lowLess common, but worth ruling out after the more likely causes.
Related help
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