P0660 Intake Manifold Tuning Valve Control Circuit/Open Bank 1
The intake manifold tuning valve switches the manifold length or plenum connection with engine speed (more torque low, more power high); it is not the runner or swirl flap (IMRC, P2004 ff). P0660 means the control circuit of the bank 1 (or only) valve is open. GM evaluates the line voltage with the driver off: too low means the supply through the coil is missing (200 kΩ or more). GM's engines with this valve (low-side driver) check with ignition voltage of at least 11 V and the engine above 400 rpm and set the code after 40 of 50 samples (about 0.6 s), with the check engine light after two trips. Ford uses P0660 (older: P1549) as the electrical check of its actuator, which has no position feedback and stays closed and unpowered below about 2600 rpm – without the check engine light (5 s). The valve then stays in its rest position and power at high revs suffers.
Likely causes
Symptoms
- Check engine light (GM after two trips; Ford without)
- Less power in the upper or middle rev range
- Actuator does not click at ignition on or when switching
Repair estimate
Typical range across vehicles; the real cost depends on what the testing finds.
Parts involved
Related codes
References: law.cornell.edu, gsi.ext.gm.com, gsi.ext.gm.com, gsi.ext.gm.com.