P2017 Code: Intake Manifold Runner Position Sensor/Switch Circuit High (Bank 1)

What the P2017 code means

Many modern engines carry extra flaps inside the intake manifold, separate from the throttle body. Their job is to change the geometry or the turbulence of the incoming air according to engine speed: at low rpm a faster, more turbulent flow works best, and at high rpm a more direct one.

The system is known as intake manifold runner control, and an actuator commanded by the computer moves it. A position sensor reports where the flaps really ended up.

The P2017 code is stored when the signal from that sensor goes above the expected maximum on bank 1. It is an electrical code, but its most frequent cause is mechanical.

The reason is location. These flaps work inside the manifold, exposed to the oil vapors from the crankcase and, on engines with exhaust gas recirculation, to the soot from the EGR. With mileage a pasty deposit forms that slows them down or locks them. When they cannot move, the actuator strains, the sensor ends up outside its expected range and the code appears.

It is worth knowing why these flaps exist, because it helps explain the repair. At low rpm the engine draws little air, and if it comes in through a wide passage it moves slowly and mixes poorly with the fuel. Partly closing the passage speeds that air up and creates turbulence, which improves the mixture and the torque at low rpm. At high rpm the opposite is needed: the maximum possible airflow, and the flaps open all the way.

That is why the typical symptom of this code is a loss of strength right down low, which is where these flaps really do their work.

P2017 code symptoms

• Check engine light on.
• Loss of power, more noticeable at low rpm.
• Rough idle.
• Higher fuel use.
• Jerking or hesitation when you accelerate.
• Actuator noise when you turn the key on or accelerate.
• May appear together with actuator codes or bank 2 codes.
• The loss of strength is most noticeable pulling away from a stop and at low rpm.

Likely causes of the P2017 code

1. Carbon buildup on the flaps and their shafts, which keeps them from moving freely. The dominant cause.
2. Bad system actuator or one with damaged gears.
3. Defective position sensor.
4. Internal linkage disconnected or broken.
5. Signal wire shorted to a voltage line.
6. Sensor ground open or with high resistance.
7. Corroded connector or backed-out pins.
8. Too many crankcase oil vapors, which speed up the deposits.
9. EGR valve adding too much soot.

How to diagnose the P2017 code step by step

1. Check the sensor reading with the key on and see whether it responds when you run the system with an active test.
2. Listen to the actuator when you turn the key on. A strained sound, or no sound at all, points toward the mechanical side or the electrical side.
3. Check the linkage movement by hand with the engine off, if you can reach it. It should travel through its range smoothly with no binding.
4. Remove the intake manifold and inspect the flaps if the movement is stiff. The deposits are usually visible to the naked eye.
5. Measure the sensor ground and its voltage drop.
6. Unplug the sensor and watch the reading. If the high voltage stays, the problem is in the wiring.
7. Check the crankcase ventilation system, which is the source of the oil vapors.
8. Check for equivalent codes on bank 2.
9. Find out at what rpm the power loss shows up. If it is at low rpm, it fits a fault in these flaps. If it is at high rpm, look elsewhere.

How to fix the P2017 code

• Clean the manifold flaps and their shafts with a dedicated product, removing the deposits completely.
• Replace the actuator if its gears are damaged or it does not respond to the active test.
• Replace the position sensor if the circuit is correct and it still gives an impossible signal.
• Repair the internal linkage if it is disconnected or broken.
• Correct the sensor ground and any damaged wiring.
• Change the oil separator or the crankcase ventilation valve if it is sending too many vapors.
• Deal with the EGR valve if it is adding too much soot.
• After the cleaning, verify that torque at low rpm has come back, because that is where these flaps do their work.

On some engines the flaps are not sold separately and the whole manifold has to be replaced. Check that availability before you quote the job.

Technical reference data

• The manifold flaps change the geometry or the turbulence of the air according to engine speed.
• Typical position sensor signal: 0.5 to 4.5 volts.
• The code is set when the signal goes above the upper end of the scale.
• Bank 1 is the side of the engine that contains cylinder number one.
• The deposits come from crankcase oil vapors and EGR soot.
• On some engines the flaps are not sold separately from the manifold.
• Closed flaps speed up the air and create turbulence at low rpm. Open flaps give maximum airflow at high rpm.

Brand-specific notes

The most useful thing you can do before ordering parts is to check whether the linkage moves freely. If it is stiff or seized, the problem is carbon, and no new sensor or actuator will fix it as long as the flaps stay locked.

If the P2017 code comes back a few months after a cleaning, check the crankcase ventilation system and the condition of the EGR. They are the two routes the deposits arrive by, and without dealing with them the cleaning is only a postponement.

Frequently asked questions about P2017