The configuration of the DTC P2004 OBD2 code implies that the Intake Manifold Control (IMCR) is stuck in the open position.
The Powertrain Control Module (PCM) provides the IMRC with information related to current driving conditions. The IMRC relies on this data to regulate the amount of airflow that will be allowed into the intake system. With these intake airflow regulations, harmful emissions are reduced and a better air/fuel mixture is obtained. Besides, there is higher fuel efficiency.
The causes of the problem code P2004 OBDII are the following:
The IMRC actuator solenoid may be damaged.
Damage to the IMRC actuator circuit
There may be maladjusted manifold corridors.
The Intake Manifold Control Sensor (IMRC) may be defective.
The Manifold Absolute Pressure (MAP) Sensor may be in poor condition.
Possible solutions of the DTC code P2004 Generic
The steps to solve the problems related to the P2004 OBD2 diagnostic code are
Make a query of the Technical Service Bulletins (TSB).
Check the system of the cables by their connectors. These connectors are exposed to a high percentage of corrosion, so you must pay special attention to them. Repair as required.
Check the IMRC actuator solenoid and the Intake Manifold Control Sensor (IMRC). You should make voltage, resistance, and continuity tests on their circuits and compare the results to the manufacturer's specifications. Replace the solenoid or sensor if they do not meet those specifications.