P2006 Code: Intake Manifold Runner Control Stuck Closed (Bank 1)

What the P2006 code means

Many engines have flaps or valves in the intake manifold (IMRC, Intake Manifold Runner Control, also called swirl or tumble flaps) that change the length or shape of the intake runner. At low rpm they close so the air enters faster and with more turbulence, which improves torque and combustion. At high rpm they open to let more air through. An electric motor or a vacuum actuator controlled by a solenoid moves them, and a position sensor tells the computer whether they really moved.

When the computer commands the flaps open and the sensor keeps showing the closed position for the programmed time, it stores the P2006 code. Bank 1 is the side of the engine where cylinder number 1 is. Inline engines only have bank 1. On V engines, bank 2 is the opposite side.

The cause is almost always mechanical: carbon or crankcase ventilation oil jamming the flap shaft, a loose or broken actuator rod, or a cracked vacuum hose. An electrical failure of the actuator is less common.

The engine keeps running, but it loses torque in the range where the flaps should be in the other position. With the flaps stuck closed, you notice it mostly when accelerating at high rpm.

P2006 code symptoms

• Check engine light on.
• Loss of power at mid and high rpm.
• Slightly uneven idle on some engines.
• A small increase in fuel use.
• A rattling or clicking noise in the manifold if a flap has come loose.

Likely causes of the P2006 code

1. Flap shaft jammed by carbon. The most frequent cause, especially on diesels and high-mileage engines.
2. Actuator rod or ball joint loose or broken. The actuator moves but does not drag the flaps along.
3. Vacuum hose or reservoir leaking on pneumatic actuators.
4. Control solenoid or electric actuator bad. It does not respond to the command.
5. Position sensor out of adjustment. It reports a position that is not the real one.

How to diagnose the P2006 code step by step

1. Read the live data: commanded position and actual position of the flaps.
2. Activate the flaps with the scan tool and watch the movement of the rod or the shaft.
3. Turn the shaft by hand with the engine off. It should rotate without tight spots through its full travel.
4. Check the vacuum with a vacuum gauge at the actuator hose, on pneumatic systems.
5. Inspect the rod and the ball joint. They tend to pop out or break.
6. Measure power and control at the actuator if it is electric.

How to fix the P2006 code

• Clean the manifold and the flap shaft if they are jammed.
• Replace the broken ball joint or rod. Repair kits exist for many engines.
• Replace the actuator if it does not move with correct power and control.
• Some manufacturers only sell the complete manifold with the flaps.
• Clear the codes and confirm with the scan tool that the actual position follows the commanded one.

Technical reference data

• Vacuum actuator: it should hold about 15 to 20 inHg without losing vacuum for one minute.
• Electric actuator: 12 volt supply, with control by a PWM signal or by reversing polarity.
• Position sensor: 5 volt reference and a signal of roughly 0.5 to 4.5 volts depending on the flap position.
• These values are only a guide, so look up the manufacturer data for your vehicle.

Brand-specific notes

On some diesels the flaps fill up with carbon and can break. A fragment inside the cylinder can cause a serious failure, so some shops remove the flaps following manufacturer procedures.

P2006 on Ford and Mazda

This code is frequent on Ford Duratec and Mazda MZR gasoline engines.

P2006 on Volkswagen, BMW, Mercedes-Benz and Fiat

It is also frequent on the diesel engines with swirl flaps from Volkswagen, BMW, Mercedes-Benz and Fiat.

P2006 on GM V6 Engines

Several GM V6 engines are also known for this code.

Frequently asked questions about P2006