Intake Manifold Tuning Valve Control Circuit Low (Bank 2)
The engine computer detected a weak electrical signal from the intake manifold tuning valve on bank 2, similar to a dimmed light bulb that should be bright. This valve controls airflow to optimize engine performance, and a low signal means the computer can't properly command it.
The ECU monitors the control circuit voltage to the intake manifold tuning valve solenoid on bank 2. It expects sufficient voltage and current flow when commanding the valve open or closed. A low voltage condition indicates a wiring fault, poor connection, or internal solenoid failure.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Control Circuit Voltage | 10.5–14.5 V during command | Below 4 V or no signal detected |
| Solenoid Resistance | 5–15 ohms | Open circuit or excessive resistance |
Code P0664 is a moderate fault. You can generally drive to a workshop, but avoid long trips or high-load driving (motorway, uphill towing) until it is diagnosed. If the code keeps returning after clearing, or if you notice the symptoms listed above worsening, do not delay professional diagnosis. Many moderate codes have multiple possible root causes — a mechanic with live OBD data can identify the exact fault more efficiently than part-by-part trial and error.
Once the fault is repaired, P0664 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.