Intake Manifold Runner Control Circuit/Open Bank 1
Diagnostic trouble code P2008 indicates that the powertrain control module (PCM) has detected an open electrical circuit in the Intake Manifold Runner Control (IMRC) system for Bank 1. This means the PCM cannot properly communicate with or control the actuator that adjusts the intake manifold runner flaps to optimize airflow.
While not an immediate safety hazard, this issue can cause poor engine performance, reduced fuel economy, and increased emissions. It should be diagnosed and repaired soon to restore proper engine operation and prevent potential long-term catalytic converter stress.
Common symptoms
- Illuminated Check Engine Light
- Rough or fluctuating engine idle
- Hesitation or stumbling during acceleration
- Reduced low-end engine torque and power
- Decreased fuel efficiency
Likely causes
- Disconnected, damaged, or corroded wiring harness to the IMRC actuator
- Faulty Intake Manifold Runner Control (IMRC) solenoid or actuator
- Poor electrical connection at the IMRC valve
- Physically binding or broken intake manifold runner flaps causing circuit overload
- Failed Powertrain Control Module (PCM) (rare)
What to check before replacing parts
Inspect the IMRC actuator wiring and connector on Bank 1.
Look for: Look for frayed wires, melted insulation, backed-out pins, or heavy corrosion inside the connector that would cause an open circuit.
Command the IMRC actuator using a bi-directional scan tool.
Look for: Listen for an audible click or observe the physical linkage moving. If it does not move, the circuit is open or the actuator has failed.
Test the internal resistance of the IMRC solenoid/actuator using a multimeter.
Look for: An infinite resistance (OL) reading indicates an open internal coil, meaning the actuator itself must be replaced.
Check for proper voltage and ground at the IMRC connector.
Look for: With the key on, engine off (KOEO), verify that the connector receives the manufacturer-specified reference voltage and a good ground. Missing voltage indicates a wiring or PCM issue.
Manually actuate the intake manifold runner linkage.
Look for: Disconnect the actuator arm and move the flaps by hand. If they are stuck or binding heavily with carbon buildup, the manifold may need cleaning or replacement, which could have caused the actuator to fail.
This page explains the generic P2008 definition and is general reference information, not a diagnosis for your specific vehicle. Actual causes, severity, and repairs vary by make, model, engine, and mileage — always confirm with a scan tool and a qualified technician before replacing parts.
Gear guide: Best OBD2 ScannersRead this code yourself next time — from $20 Bluetooth dongles to bidirectional scan tools.Rather have a pro handle it? Find a vetted local mechanic.