How much does it cost to fix P2004?

DIY repair typically costs $15–$150 for parts. Professional repair runs $150–$600 including parts and labor.

P2004

Powertrain

Moderate

Intake Manifold Runner Control Stuck Open (Bank 1)

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The P2004 code means your vehicle's powertrain control module (PCM) has detected that the intake manifold runner control (IMRC) valve on bank 1 is stuck in the open position. The IMRC system uses butterfly valves inside the intake manifold to vary the effective length of the intake runners, optimizing airflow at different engine speeds for better performance and fuel economy.

When the IMRC valves are stuck open, the engine loses the ability to optimize airflow at lower RPMs, which typically results in reduced low-end torque, rough idle, and decreased fuel efficiency. The most common culprit is carbon buildup on the butterfly valves, particularly in direct-injection engines.

While you can usually continue driving with this code, it's important to address it within a week or two. In rare cases, the IMRC hardware can become loose and fall into the engine, which could cause severe and costly engine damage. A mechanic can clean the carbon deposits, replace the actuator solenoid, or repair any vacuum line issues. DIY-friendly owners can often inspect and clean the IMRC valves themselves with intake cleaner and basic tools.

Severity

Moderate — Address SoonThis Week

Symptoms

•Check engine light is on
•Noticeable loss of engine power especially at lower RPMs
•Rough or unstable idle
•Poor fuel economy
•Possible engine hesitation during acceleration

Likely Causes

Carbon buildup on IMRC butterfly valves35%

Over time, carbon deposits accumulate on the intake manifold runner control butterfly valves, causing them to stick in the open position. This is especially common in direct-injection engines where fuel does not wash over the intake valves to keep them clean.

Faulty IMRC actuator or solenoid30%

The electrically-controlled solenoid or vacuum actuator that moves the runner valves can fail due to heat exposure, corrosion, or internal component wear, leaving the valves stuck in the open position.

Broken or disconnected vacuum lines20%

In vacuum-operated IMRC systems, cracked, disconnected, or deteriorated vacuum hoses prevent the actuator from receiving the vacuum signal needed to close the runner valves.

Wiring or connector issues in the IMRC circuit15%

Corroded connectors, damaged wiring, or poor electrical connections to the IMRC solenoid can prevent the actuator from receiving the proper control signal from the PCM.