P2004: Intake Manifold Runner Control Stuck Open (Bank 1)

What does P2004 mean?

The bank 1 intake runner system stays open when it should change position. Runner flaps alter airflow behavior, so being stuck open often affects low-speed performance more than an ordinary intake sensor circuit fault.

Generic OBD-II definition: Intake Manifold Runner Control Stuck Open (Bank 1). Confirm applicability in your vehicle service information.

Common causes

• Binding or loose runner linkage
• Failed runner actuator or vacuum control
• Inaccurate position feedback or damaged wiring

Symptoms

• Weak low-RPM response
• Surging
• Reduced fuel economy

Diagnostic focus

A position report alone may not prove the flaps actually move. Inspect linkage condition and use the approved actuator test rather than forcing the mechanism by hand.

Can I keep driving with P2004?

Severity: Medium Drive gently and get it diagnosed soon.

If the check engine light is flashing or the car runs badly, stop driving and have it checked.

Typical fixes

• Inspect external linkage and vacuum hoses if fitted
• Compare commanded and actual runner position
• Test the actuator and feedback before manifold replacement

Sources & review

• OBD-Codes.com: P2004
• TroubleCodes.net: P2 code definitions

Definitions and diagnostic background checked 2026-11-06. Generic guidance, not a substitute for the service procedure for your exact year, engine, and transmission.