This code indicates that the engine computer has detected a performance problem within the circuit that controls the intake valve deactivation for cylinder 6. It means the system designed to shut down that specific cylinder to save fuel is not engaging or disengaging correctly. The root cause is almost always related to oil flow issues affecting the variable cylinder management hardware rather than an electrical failure.
The spool valve or solenoid that directs oil pressure to deactivate cylinder 6 can become stuck or fail internally due to sludge and oil contamination.
These systems rely on precise oil pressure to actuate the valves; a low oil level or using the wrong viscosity oil can prevent the system from functioning properly.
Restricted oil passages leading to the cylinder 6 deactivation solenoid or lifter will starve the system of the hydraulic pressure needed for valve control.
The mechanical hydraulic lifter that physically disconnects the intake valve can fail, collapse, or stick, preventing the cylinder from changing modes.
Corroded, disconnected, or shorted wiring and connectors in the cylinder 6 intake valve control circuit can disrupt the signal needed for proper solenoid operation.
The engine computer is rarely the cause of this specific code, as it is almost always triggered by a mechanical or hydraulic failure in the deactivation system.
You can typically drive cautiously, but the engine may run rough, misfire, or lack full power. It is best to diagnose it promptly to prevent potential damage to the valve train from a stuck lifter.
No, replacing the PCM is almost never the correct fix for this code. The problem is almost always caused by a lack of oil pressure to the system, a stuck solenoid, or a mechanical lifter failure, not a computer failure.
Yes, oil sludge or contaminated oil is a very common cause. The cylinder deactivation system relies on tiny passages and solenoids that can easily become stuck or clogged by poor-quality or infrequently changed engine oil.
Cylinder deactivation systems shut down specific cylinders during steady cruising to improve fuel economy and reduce emissions. When more power is needed, the system rapidly reactivates those cylinders.