P2009: Intake Manifold Runner Control Circuit Low (Bank 1)

P2009 narrows the bank 1 flap control fault down to a low signal, which in practice means the control line has found a path to ground. GM's 2018 diesel tables flag a resistance to ground below 0.5 Ω in 12 of 15 checks every 100 ms (Type B), and the 2014 Cruze diesel waits until the short has lasted more than 3 s. In GM's 2025 DC-motor swirl drive the H-bridge is switched on and the code sets when its current exceeds 8 A in 240 of 300 samples. On the 2010 Saab 9-5 diesel the ECM uses P2009 for a grounded control circuit of the swirl solenoid. Subaru lists P2009, together with P2012 for bank 2, among codes on 2017–2020 Impreza and Crosstrek where grease from the tumble valve actuator leaks into the engine; the actuator is not sold alone, so the manifold is replaced. A chafed harness or water in the plug are the usual causes.

Medium severity. Can I keep driving?You can drive in moderation. Get it repaired soon, because a loose flap can cause major damage on some engines.

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

Symptoms

Malfunction indicator lamp on
Flaps cannot be switched, uneven running at low speed

Most likely causes

Control wire chafed through and touching ground
Internal short in the solenoid or actuator motor
Leaking integrated tumble valve actuator (Subaru Impreza/Crosstrek)
Water or corrosion in the actuator connector

What to check, in order

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

Check the vacuum hoses and the connector
With the connector unplugged, check whether the signal wire is making contact with ground.
Watch the actuator's movement with the scanner
Inspect the manifold for carbon buildup
Replace the actuator if it does not follow the command

Good to know

Repair difficulty: medium
It affects emissions.

What each character of P2009 means

P: Powertrain: engine and transmission
2: Generic code: same on every make
0: Subsystem depends on the code range
09: Specific fault in that system

Frequently asked questions

Can I keep driving with code P2009?

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

What causes code P2009?

The most common causes are: control wire chafed through and touching ground; internal short in the solenoid or actuator motor; leaking integrated tumble valve actuator (Subaru Impreza/Crosstrek).

Related codes

Sources

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.