Intake Manifold Tuning (IMT) Valve Position Sensor/Switch Circuit High Bank 1
What it means
P2078 means the intake manifold tuning valve position sensor on bank 1 is reporting a voltage that is too high, usually from a short-to-power or open. This sensor tells the PCM where the tuning valve is set. A bad reading can slightly affect intake tuning and power in part of the rev range, but it does not cause a no-start. The engine runs and starts normally.
Can I keep driving? Drivable, though power may feel down in part of the rev range; not urgent, but worth fixing to restore full response.
Real-world scan data
Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.
Common symptoms
What you'll notice
- Check-engine light on
- Reduced power or hesitation in part of the rev range
- Slightly rough idle
- Minor drop in fuel economy
Common causes
Most likely first
- IMT valve position sensor circuit shorted to power or openLikely
- Faulty intake manifold tuning valve position sensor/switchCommon
- Damaged wiring or corroded connector at the valveCommon
- Faulty or stuck intake manifold tuning valve reporting an out-of-range positionLess often
- Faulty PCM (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and inspect the valve wiring and connector for shorts or corrosion.
- Check the position sensor's signal voltage against the valve's actual position with a scan tool.
- Repair any short-to-power or open in the circuit.
- Replace the IMT valve or its position sensor/switch if the signal stays high.
- Clear the code and re-test; consider the PCM only after wiring checks out.
FAQ
Quick answers
Is it safe to drive with P2078?+
Can I just clear P2078?+
Related codes
Read & clear P2078 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.