Damaged, chafed or corroded wiring to the tuning valve solenoid or actuator (open circuit or high resistance); Poor connection at the valve connector, including corroded, loose or pushed-out terminals; Failed tuning valve solenoid or actuator with an open internal coil or motor winding; Blown fuse or loss of power or earth supply to the valve circuit; Sticking or seized intake flap mechanism overloading the actuator (depends on engine design); Faulty engine control unit output driver.

P0660

Intake Manifold Tuning Valve Control Circuit/Open Bank 1.

Generic
Powertrain
Generic code
Low severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
6: AreaComputer and output circuits
60: FaultThe specific fault in that area

What it means

P0660 is the generic code for a fault in the control circuit of the intake manifold tuning valve on bank 1. The valve changes the length or routing of the intake runners to improve torque and power across the rev range. The engine control unit sets the code when the voltage or current it sees on the valve's control circuit does not match what it commanded, typically an open circuit.

Symptoms

Malfunction indicator lamp on
Loss of power or flat spot at certain engine speeds
Reduced torque in the low or high rev range
Poorer fuel economy
Rough running or hesitation under load
Whistling or hissing noise from the intake if a vacuum line is involved

Possible causes

Damaged, chafed or corroded wiring to the tuning valve solenoid or actuator (open circuit or high resistance)likely
Poor connection at the valve connector, including corroded, loose or pushed-out terminalslikely
Failed tuning valve solenoid or actuator with an open internal coil or motor windinglikely
Blown fuse or loss of power or earth supply to the valve circuitpossible
Sticking or seized intake flap mechanism overloading the actuator (depends on engine design)possible
Faulty engine control unit output driverrare

How to diagnose

Read all stored codes and freeze frame data, then note whether the code is current or intermittent and whether other codes are present
Check the technical data for the engine to find out whether the valve is a vacuum solenoid, an electric actuator or a motor, as testing differs
Visually inspect the valve, its connector and the wiring along its route for chafing, heat damage, corrosion and water ingress
Check the relevant fuse and confirm there is a supply voltage and a good earth at the valve connector with the ignition on
Measure the valve coil or motor resistance and compare it with the manufacturer specification
Command the valve with a bidirectional scan function if available and listen for or watch the movement, checking the control signal at the connector
Check for continuity and short circuits in the wiring between the valve and the control unit, with the connectors disconnected
Where it is fitted, inspect the vacuum lines and the flap mechanism for leaks, binding or carbon build-up

How to fix

Repair or replace damaged wiring and fix any faulty connector terminals
Replace the intake manifold tuning valve solenoid or actuator if it fails the electrical tests
Restore the fuse, power or earth supply and find out why it failed
Free or replace a binding flap mechanism, which on some engines means replacing the intake manifold assembly
Repair the control unit only after the wiring and valve have been proven good, and follow the manufacturer's procedure
Clear the code after the repair and road test to confirm it does not return

Can I keep driving?

Low severity

The car can usually be driven in the short term as the engine will run with the valve in its default position, but expect reduced performance and economy. Book it in soon, and stop if the engine runs very roughly or other warnings appear.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.