P2004
Intake Manifold Runner Control Stuck Open Bank 1
Intake air (manifold runner control)
Generic OBD-II
High
What it means
P2004 means the intake manifold runner control flaps on bank 1 are stuck in the open position. These flaps tune intake airflow for low-rpm torque, so when they're stuck open the engine can feel flat off idle and lose a little economy. Carbon build-up or a failed actuator or solenoid is the usual cause.
High
Can I keep driving? Usually drivable — the car runs but may feel flat at low rpm and use a little more fuel; fix it to restore low-end response and clear the light.
Common symptoms
What you'll notice
- Check-engine light on
- Weak low-speed torque or sluggish acceleration off idle
- Slightly rough idle in some engines
- Minor drop in fuel economy
Common causes
Most likely first
- Intake runner flaps or linkage stuck open by carbon build-up (most common)Likely
- Failed intake manifold runner control (IMRC) actuatorCommon
- Faulty IMRC control solenoid or blocked vacuum supplyCommon
- Broken, disconnected, or leaking vacuum hose to the actuatorLess often
- Wiring, connector, or position-sensor fault in the runner-control circuitLess often
- Faulty PCM (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame and, where available, the runner-position feedback to confirm the flaps are reading open.
- Inspect the runner control linkage and flaps for carbon build-up or binding; clean as needed.
- Check the IMRC actuator's movement and its vacuum supply or electrical command.
- Test the control solenoid, its wiring and connector, and any runner-position sensor against spec.
- Repair or replace the failed actuator, solenoid, or hose, then clear and re-test.
FAQ
Quick answers
Is it safe to drive with P2004?+
Generally yes. The engine runs, though low-rpm power and economy suffer, so it's best fixed soon rather than urgently.
Can I just clear P2004?+
If the runner flaps are physically stuck, the code returns quickly. Free or repair the runner control first, then clear it.
Related codes
Often seen with P2004
Read & clear P2004 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX