What Does P3406 Mean?
The PCM has detected that cylinder 1's exhaust valve control system is not responding correctly or within expected parameters. The solenoid is receiving commands but the actual valve timing/lift response is outside acceptable range.
Common Causes
35%
Mechanical failure of exhaust valve actuator or lifter
25%
Low engine oil level or incorrect oil viscosity affecting hydraulic operation
20%
Sludge or carbon buildup restricting valve actuator movement
15%
Weak or failing exhaust valve control solenoid
5%
Clogged oil passages to valve actuator
Diagnostic Steps
1
Step 1: Check engine oil level and condition; verify correct viscosity specification is being used
2
Step 2: Monitor live data for exhaust valve actuator position vs commanded position on cylinder 1
3
Step 3: Perform oil pressure test to verify adequate pressure to valve control system
4
Step 4: Inspect exhaust valve actuator for mechanical binding or damage (may require valve cover removal)
5
Step 5: Check for internal engine sludge; consider engine flush if excessive deposits found
Estimated Repair Cost
$300 - $1,500
Parts + labor, varies by vehicle and location
The PCM has detected that cylinder 1's exhaust valve control system is not responding correctly or within expected parameters. The solenoid is receiving commands but the actual valve timing/lift response is outside acceptable range.
The most common cause of P3406 (Cylinder 1 Exhaust Valve Control Circuit Performance) is: Mechanical failure of exhaust valve actuator or lifter
Typical repair costs for P3406 range from $300 to $1,500, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Vehicle can be driven but may have poor performance, rough idle, and increased emissions. Continued operation may cause catalytic converter damage or additional engine wear.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P3406 to identify the root cause.
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Quick Info
Category
Powertrain
System
Variable Valve Timing/Lift System
Difficulty
Type
Generic (SAE)
Recommended Tools
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