Intake Manifold Runner Position Sensor/Switch Circuit Low Bank 1
Diagnostic trouble code P2016 indicates that the powertrain control module (PCM) has detected a low voltage signal from the intake manifold runner position sensor or switch circuit on Bank 1. This means the sensor's output voltage has fallen below the manufacturer's specified minimum threshold, suggesting a potential short to ground or a faulty sensor.
While this code rarely causes a vehicle to stall or become undrivable, it can lead to reduced engine performance, poor fuel economy, and increased emissions. It should be diagnosed and repaired soon to restore optimal engine efficiency.
Common symptoms
- Illuminated Check Engine Light
- Reduced engine power or sluggish acceleration
- Rough idle or engine hesitation
- Decreased fuel efficiency
- Poor cold start performance
Likely causes
- Faulty intake manifold runner position sensor/switch
- Wiring harness shorted to ground or damaged in the sensor circuit
- Corroded, loose, or damaged electrical connector at the sensor
- Binding or stuck intake manifold runner flaps
- Vacuum leak affecting the intake manifold runner control actuator
- Faulty Powertrain Control Module (PCM) (rare)
What to check before replacing parts
Visually inspect the wiring and connector for the intake manifold runner position sensor on Bank 1.
Look for: Look for chafed wires, melted insulation, or a corroded/loose connector that could cause a short to ground or poor connection.
Check the sensor's reference voltage and ground circuits using a digital multimeter.
Look for: With the key on, engine off, verify that the sensor is receiving the correct reference voltage (usually 5 volts) and has a solid ground. A missing voltage or poor ground indicates a wiring issue.
Test the intake manifold runner position sensor signal voltage.
Look for: Back-probe the signal wire and monitor the voltage while manually or electronically actuating the runner flaps. The voltage should change smoothly; if it remains stuck low, the sensor is likely faulty or there is a short to ground.
Manually inspect the intake manifold runner flaps for binding or sticking.
Look for: Disconnect the actuator linkage and move the flaps by hand. They should move freely without excessive resistance. If they are stuck, the manifold may need cleaning or replacement.
Test the intake manifold runner control actuator operation.
Look for: Apply vacuum or use a scan tool to command the actuator. Verify that the actuator moves the linkage fully and holds position. A failed actuator can prevent the flaps from moving, causing the sensor to read an incorrect position.
This page explains the generic P2016 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.
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