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.

Bank 1 is the side of the engine with cylinder 1. Inline engines only have this bank.

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

Most likely causes

• Actuator connector loose, corroded or spread
• Actuator coil or motor open internally
• Broken or chafed wire (control or supply)
• Supply (fuse, main relay) to the actuator missing
• Output driver in the engine module faulty

What to check, in order

Start with the simplest. You can tick off each step.

1. Check the vacuum hoses and the connector
2. Check the continuity of the wire between the component and the control module.
3. Watch the actuator's movement with the scanner
4. Inspect the manifold for carbon buildup
5. Replace the actuator if it does not follow the command

Good to know

• Repair difficulty: easy
• It affects emissions.

What each character of P0660 means

• P: Powertrain: engine and transmission
• 0: Generic code: same on every make
• 6: Control modules and outputs
• 60: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0660?

You can drive in moderation. Get it repaired soon, because a loose flap can cause major damage on some engines.

What causes code P0660?

The most common causes are: actuator connector loose, corroded or spread; actuator coil or motor open internally; broken or chafed wire (control or supply).

Related codes

• P0661Intake Manifold Tuning Valve Control Circuit Low Bank 1
• P0662Intake Manifold Tuning Valve Control Circuit High Bank 1
• P0663Intake Manifold Tuning Valve Control Circuit/Open Bank 2
• P065EIntake Manifold Tuning Valve Performance Bank 1
• P2070Intake Manifold Tuning (IMT) Valve Stuck Open (Bank 1)
• P2071Intake Manifold Tuning (IMT) Valve Stuck Closed (Bank 1)

Sources

• law.cornell.edu: 13 CCR 1968.2
• gsi.ext.gm.com: 18OBDG03A Engine Diagnostics
• gsi.ext.gm.com: 16OBDG03 Engine Diagnostics
• gsi.ext.gm.com: 15OBDG02 Engine Diagnostics

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.