Possible Causes
- Faulty intake manifold tuning valve position sensor/switch
- Open or shorted sensor harness
- Poor electrical connection in sensor circuit
- Faulty intake manifold tuning valve (IMTV)
- Faulty intake manifold runner control (IMRC)
- Faulty powertrain control module (PCM)
Possible Symptoms
- Illuminated check engine light
Meaning of Code P2079
The intake manifold tuning valve (IMTV) is a motorized unit mounted on the intake manifold. It controls a shutter that regulates airflow into the engine.
At low RPM (below 2600 RPM), the shutter is closed to improve engine efficiency. Above this RPM, it opens under PCM control. A malfunction can prevent this adjustment, leading to performance loss.
Diagnosis and Repair
- Visual Inspection: Check electrical harness and connectors for damage.
- IMTV Sensor Test: Verify voltage and continuity using a multimeter.
- IMTV Valve Inspection: Ensure mechanical operation without obstruction.
- PCM Check: If all other components are functional, the issue may be with the engine control module.
Conclusion
Codes P2009, P092C, and P2079 indicate critical malfunctions that can affect engine and transmission performance. Thorough inspection and accurate diagnosis will resolve these issues and ensure proper vehicle operation.