P3470 indicates that the engine control module has detected a performance problem in the exhaust valve control circuit for cylinder 9. This circuit operates the variable valve timing (VVT) or cylinder deactivation actuator that adjusts exhaust valve timing, and the code sets when the actuator does not respond as commanded.
The solenoid or actuator that moves the exhaust valve timing mechanism may be stuck, electrically open, or mechanically worn, preventing proper operation.
Corroded, broken, or shorted wires and poor connector contacts can interrupt the control signal or power supply to the actuator.
Low oil level, wrong viscosity, or sludge can prevent the hydraulic actuator from moving the camshaft correctly.
Carbon buildup, wear, or damage to the phaser or related hardware can restrict movement even if the solenoid functions.
A rare internal driver or software issue in the control module could cause incorrect command signals, but this is only considered after all other causes are ruled out.
No. The PCM is rarely the root cause; most often the fault lies in the actuator, its wiring, or oil‑related issues. Replace the PCM only after all other possibilities have been eliminated.
Yes. Insufficient oil pressure or contaminated oil can prevent the hydraulic VVT actuator from moving, triggering a performance code.
Clearing the code only turns off the light temporarily. The underlying fault will cause the code to return until the defective component or condition is corrected.
Yes. An active P3470 will cause a vehicle to fail an OBD‑II emissions inspection because it indicates a malfunction in the valve timing control system.