P0660 — Intake Manifold Tuning Valve Control Circuit/Open

The diagnostic trouble code P0660 indicates an issue with the control circuit of the **Intake Manifold Tuning Valve (IMTV)**. This component is responsible for adjusting the intake manifold’s airflow to optimise engine performance and efficiency. When this code appears, it suggests that the engine control unit (**ECU**) has detected an abnormality in the electrical circuit controlling this valve.

Note: **Labels and terminology may vary between manufacturers**, but most will reference the component as the **Intake Manifold Tuning Valve** or similar.

Fast Facts

System affected: Intake Manifold / Air Intake

Severity: Moderate — requires diagnosis and repair to prevent potential drivability issues

Main symptoms: Rough idling, reduced fuel economy, engine warning light

Driveability: Limited — vehicle can often be driven but may experience performance issues

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Manufacturer variations for trouble code P0660

Many vehicle manufacturers have their own specific codes and labelings for issues related to the **Intake Manifold Tuning Valve control circuit**. These variations depend on the OEM’s coding system and nomenclature, yet they typically point to similar hardware or circuit problems. Here are some known label variations:

Volkswagen / Audi / Skoda / SEAT: P2015 – “Intake Manifold Runner Control Circuit (Bank 1)”
BMW: 2A51 – “Intake Manifold Runner Control, Circuit/Open”
Ford: P2015 or P2009 – “Variable Intake Runner Control Circuit/Performance”
Mercedes-Benz: Specific labels differ but generally relate to the control circuit malfunction of intake manifold components.

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What does trouble code P0660 mean?

P0660 is a generic OBD-II code indicating a problem within the **circuit that controls the Intake Manifold Tuning Valve**. Essentially, the ECU monitors the electrical circuit powering the valve. When it detects a problem—such as an open circuit, short circuit, or other electrical fault—it sets this code.

The **Intake Manifold Tuning Valve** itself is designed to adjust the airflow within the intake manifold, optimizing engine performance across different RPM ranges. It is usually controlled by an electric motor or actuator connected to an electrical circuit monitored by the ECU.

This code is triggered when the ECU detects that the control circuit’s voltage or resistance falls outside predefined parameters, indicating a possible wiring problem, faulty valve, or malfunctioning actuator.

Typical context of appearance: This code might appear during routine emissions testing, after a repair, or during regular driving when a sensor monitoring the valve’s circuit detects an anomaly.

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Severity and risks of trouble code P0660

The **severity** of P0660 is generally deemed **moderate**. While it may not cause immediate engine failure, it can lead to **poor engine performance**, **reduced fuel efficiency**, and increased emissions if not addressed.

Potential **risks** include:
– Diminished engine power or torque during acceleration
– Increased fuel consumption
– Rough idling or stalling conditions in some cases
– Possible damage if the issue stems from an electrical short that could affect other engine systems

**Can the vehicle be driven?** In most cases, yes — with limited driveability. However, prolonged driving without repairs may worsen engine performance and emissions compliance.

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Symptoms of trouble code P0660

Customers may notice a variety of symptoms related to this fault, often linked to the **compromised function of the intake manifold system**. Common symptoms include:

Rough idle: The engine may idle unevenly or vibrate more than usual.
Reduced power: Notable loss of acceleration or responsiveness, especially at lower RPMs.
Decreased fuel economy: Increased fuel consumption over time.
Engine warning light: The check engine light (CEL) may be illuminated on the dashboard.
White or grey smoke from the exhaust in some cases, indicating rich fuel mixture due to malfunctioning airflow regulation.
Erratic or fluctuating engine performance: Sudden surges or drops in engine power.

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Most likely causes of trouble code P0660

Thanks to the specific nature of this fault, several causes can lead to the detection of P0660. Here are the most common causes, ranked from most to least likely:

Faulty or failing Intake Manifold Tuning Valve or actuator: Often, the component itself is damaged or the motor within the valve has failed.
Bad wiring or electrical connections: Corrosion, loose connectors, or broken wires in the control circuit can disrupt proper communication.
Blown or faulty fuse: A fuse protecting the control circuit may be blown, cutting power to the valve.
Control module or ECU malfunction: Less common, but possible if the ECU misinterprets signals or has internal faults.
Mechanical obstructions or blockages: In some cases, debris or carbon build-up may hinder the valve’s movement, although this is less common.

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How to diagnose trouble code P0660

Diagnosing this code requires a systematic approach to ensure the root cause is correctly identified. Here are generic diagnostic steps:

Visual inspection of wiring and connectors: Check for corrosion, damaged wires, loose clips, or burnt connectors around the intake manifold area.
Inspect the fuse associated with the circuit: Ensure any relevant fuses are intact and functioning.
Check live data with a scan tool: Monitor the control circuit voltage and the actuator’s response when the engine is running.
Perform continuity and resistance tests on wiring and connectors involved in the control circuit.
Command the actuator via the scan tool: If possible, activate the valve control circuit and observe for proper operation.
Inspect the intake manifold tuning valve/actuator: Remove if necessary to check for mechanical faults or obstructions.

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Possible repairs for trouble code P0660

Once the cause is identified, several repairs might be necessary. Here’s what to consider, in terms of repair types:

Replace the faulty intake manifold tuning valve or actuator: Usually a **professional repair** as it involves removing parts of the intake manifold.
Repair or replace damaged wiring or connectors: Basic repair that can often be performed by a competent DIYer or technician.
Replace blown fuses or relays: A simple, easy fix.
Reset the ECU after repairs: Clears the fault codes, but only effective if the root cause is fixed.
Address mechanical obstructions or carbon build-up: May require cleaning or mechanical intervention, usually performed by a professional.

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Vehicles commonly associated with trouble code P0660 in Europe

In Europe, this fault can appear across a variety of makes and models, especially those equipped with variable intake systems. Based on manufacturers and typical engine families, common affected vehicles include:

Volkswagen Group: 1.4 TSI, 1.8 TFSI, 2.0 TDI engines

BMW: N20, N26, B48 engines

Ford: EcoBoost 1.0L, 1.5L, 2.0L engines

Mercedes-Benz: M270/M274 engines, among others

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Frequent mistakes with trouble code P0660

Numerous technicians may encounter pitfalls when diagnosing or repairing this fault. Common mistakes include:

Assuming the problem is solely electrical without inspecting mechanical components.
Replacing parts unnecessarily without verifying the circuit’s integrity or diagnosing live data.
Ignoring possible related faults, such as other intake or air system issues that could influence the valve’s operation.
Failing to clear the fault codes after repairs, leading to confusion during test drives.
Overlooking the importance of inspecting the ECU and wiring harness thoroughly before replacing expensive components.

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FAQ — trouble code P0660

Can this code disappear on its own?

Yes, but only if the underlying issue, such as a temporary electrical glitch or loose connection, is resolved. Normally, the code persists until diagnosed and repaired.

Can I keep driving?

While you might be able to continue driving, it is recommended to address the fault promptly. Prolonged operation could lead to degraded engine performance or further damage.

Why does the code return after clearing?

This usually indicates that the root cause has not been fixed, such as wiring issues or a faulty valve. The ECU will detect the failure again and log the code during the next drive cycle.