P2004 code definition
Intake Manifold Runner Control (IMRC) Stuck Open Bank 1
Related Trouble Codes:
- P2005: IMRC Stuck Open Bank 2
- P2006: IMRC Stuck Closed Bank 1
- P2007: IMRC Stuck Closed Bank 2
- P2008: IMRC Circuit Open Bank 1
- P2009: IMRC Circuit Low Bank 1
- P2010: IMRC Circuit High Bank 1
- P2011: IMRC Circuit Open Bank 2
- P2012: IMRC Circuit Low Bank 2
- P2013: IMRC Circuit High Bank 2
- P2014: Intake Manifold Runner Position Sensor/Switch Circuit Bank 1
- P2015: Intake Manifold Runner Position Sensor/Switch Circuit Range/Perf Bank 1
- P2016: Intake Manifold Runner Position Sensor/Switch Circuit Low Bank 1
- P2017: Intake Manifold Runner Position Sensor/Switch Circuit High Bank 1
- P2018: Intake Manifold Runner Position Sensor/Switch Circuit Interm Bank 1
- P2019: Intake Manifold Runner Position Sensor/Switch Circuit Bank 2
- P2020: Intake Manifold Runner Position Sensor/Switch Circuit Range/Perf Bank 2
- P2021: Intake Manifold Runner Position Sensor/Switch Circuit Low Bank 2
- P2022: Intake Manifold Runner Position Sensor/Switch Circuit High Bank 2
- P2023: Intake Manifold Runner Position Sensor/Switch Circuit Interm Bank 2
What the P2004 code means
The P2004 diagnostic trouble code indicates that the intake manifold runner control (IMRC) is stuck in the open position on Bank 1.
The Powertrain Control Module (PCM) provides the IMRC with information relating to current driving conditions, and the IMRC uses this information to regulate the amount of airflow that is permitted into the intake system. By regulating intake airflow, harmful emissions are reduced, the air/fuel mixture is improved, and fuel economy is increased.
The components of the IMRC include:
- vacuum actuator
- electric solenoid
- butterfly valve plates
- air passageways to each cylinder
- linkage rods connected to the intake manifold butterfly plate level
- return springs that hold the butterfly valve plates open
The PCM receives information from the IMRC solenoid, mass airflow (MAF) sensor, and barometric (BARO) sensor to make a determination as to the proper position of the IMRC butterfly valve plates. The plates then open and close to allow or restrict air from entering into the intake system.
At high speeds/RPM, the IMRC butterfly valve plates will open to allow the flow of air into the intake system, and at low speeds/RPM, the IMRC butterfly valve plates will close to restrict the flow of air into the intake system. If the PCM determines that voltage reading from the IMRC solenoid, MAF sensor, and BARO sensor indicate that the IMRC butterfly valve plates are not in the proper position, it will store the P2004 trouble code.
What causes the P2004 code?
- IMRC solenoid that is defective
- IMRC solenoid wiring that has shorts, breaks, or is frayed.
- IMRC solenoid circuitry that has shorted or is open
- IMRC solenoid connector that is corroded
- IMRC butterfly valve plate screws that are loose or broken
- IMRC butterfly valve plates that are broken
- IMRC butterfly valves plates that have disconnected from the IMRC actuator
- Vacuum control solenoid vacuum filter that is clogged
- Debris in the vacuum control solenoid
- Vacuum lines that are disconnected or broken
- Carbon buildup on the IMRC butterfly valve plates
- Exhaust gas recirculation (EGR) valve trouble codes that have been stored by the PCM
- MAF sensor trouble codes that have been stored by the PCM
- BARO sensor trouble codes that have been stored by the PCM
What are the symptoms of the P2004 code?
- Decrease in fuel economy
- Decrease in low end engine torque
- The engine may surge/sputter
- The vehicle will run rough
- Check Engine/Service Engine Soon Light on
- Check Engine/Service Engine Soon Light flashing
How does a mechanic diagnose the P2004 code?
- Uses an OBD-II scanner to collect freeze frame data and any trouble codes that have been stored by the PCM (if trouble codes for the EGR valve, MAF sensor, and/or BARO sensor have been stored by the PCM, they should be diagnosed and repaired first)
- Completes a visual inspection of all wiring for shorts, breaks, and frays
- Repairs or replaces any shorted, frayed, or broken wiring
- Completes a visual inspection of the IMRC solenoid for corrosion and damage
- Repairs or replaces any corroded or damaged connectors
- Inspects the vacuum lines and hoses
- Repairs or replaces any loose or damaged vacuum lines or hoses
- Inspects the IMRC butterfly valve plates for proper connection and/or breaks
- Inspects the EGR valve for excessive carbon buildup (this carbon buildup could get onto the IMRC solenoid and render it defective)
- Clears the codes and retests to see if the P2004 trouble code returns
- Uses the scan tool to test the IMRC solenoid:
Open and close the IMRC solenoid using the scanner. If the IMRC solenoid does not respond, the solenoid will need to be replaced.
Common mistakes when diagnosing the P2004 code
- Misdiagnosing and replacing the IMRC solenoid
- Misdiagnosing and replacing the IMRC butterfly valve plates
- Overlooking damaged or disconnected vacuum lines
- Overlooking IMRC solenoid connector and wiring
- Replacing the IMRC butterfly valve plates when the problem was that they were not connected properly
- Neglecting to diagnose and repair other EGR valve, MAF sensor, and/or BARO trouble codes before making any repairs for the P2004 trouble code.
How serious is the P2004 code?
The P2004 trouble code may become serious if the hardware for the IMRC butterfly valve plates become loose and fall off into the engine. If this happens, severe engine damage is possible, and could potentially cause engine failure. It is important to have the P2004 trouble code inspected and repaired as soon as possible.
What repairs can fix the P2004 code?
- Replacing the IMRC solenoid
- Repairing or replacing IMRC solenoid wiring that has shorts, breaks or is frayed
- Repairing or replacing IMRC solenoid circuitry that has shorted or is open
- Repairing or replacing IMRC solenoid connector that is corroded.
- Repairing and/or replacing IMRC butterfly valve plate hardware, if necessary
- Repairing or replacing loose or damaged vacuum lines
- Replacing IMRC butterfly valve plates (in order to do this, the intake manifold assembly will need to be replaced)
- Diagnosing and repairing EGR valve, MAF sensor, and/or BARO trouble codes, if present
The PCM may store the P2004 trouble code if the IMRC butterfly valve plates become detached from the IMRC actuator. This code may be resolved quickly by checking the connection of the IMRC butterfly valve plates and the IMRC actuator.
It is also common for the PCM to store the P2004 trouble code because carbon buildup in the intake is causing the IMRC butterfly valve plates to become stuck.
*Need help with a P2004 code? *
YourMechanic offers certified mechanics who will come to your home or office to diagnose and repair your vehicle.
Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.
Check Engine Light
trouble codes
P2004
