What it means
IMT position sensor at bank 1 reads below lower plausibility — short to ground. The intake manifold runner control (IMRC) flaps tune intake geometry for filling efficiency across the rpm range; stuck flaps cost part-load torque and can set lean codes.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The Bank 1 intake manifold tuning valve adjusts the intake path, and its position sensor sends a signal to the engine computer. P2077 sets when that signal is below the acceptable low limit, commonly because the signal circuit is shorted to ground or has a wiring or connector fault.
Common causes
Most likely first.
- Short to ground
- Connector pins corroded - high contact resistance
- Harness chafing through insulation
Symptoms
- Check-engine light
- Possible reduced engine power or acceleration
- Possible hesitation or rough running
How to diagnose it
- Check freeze-frame and live data for the Bank 1 IMT position signal and note whether it remains at the low end despite valve commands.
- Inspect the Bank 1 sensor connector and harness for chafing, crushed insulation, corrosion, or a wire contacting ground.
- Use the vehicle wiring diagram to identify the Bank 1 sensor signal, supply, and ground wires before testing the circuit.
- Check the signal wire for a short to ground and verify sensor supply and ground integrity using the manufacturer's test procedure.
- If wiring checks pass, compare Bank 1 sensor output and tuning-valve movement with the manufacturer's specification.
Common fixes
- Repair chafed Bank 1 sensor wiring that is shorted to ground.
- Clean and secure corroded or loose terminals at the Bank 1 IMT connector.
- Repair a damaged sensor ground or signal connection.
- Replace the Bank 1 position sensor if its output remains too low with a sound circuit.
Can I keep driving?
Cautious driving may be possible if the engine remains stable, but avoid hard acceleration if it hesitates or loses power. The valve may not tune the Bank 1 intake correctly, reducing response and increasing emissions.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.