Diagnostic article Generic OBD-II
P2021: A low bank 2 runner position signal is not proof the runners are closed
Understand Ford P2021 IMRC position-sensor circuit monitoring and distinguish low electrical input from a valid closed position.
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Documented application
Ford 2024–2025 gasoline OBD operation summary, July 16 2024 revision; only the documented monitor variants. No individual model, engine or calibration fitment inferred.
The code alone does not identify a failed part or establish that a vehicle is safe to drive. Confirm the vehicle, reporting module and applicable service procedure.
P2021 identifies the bank 2 intake manifold runner position sensor circuit-low result in Ford's vacuum-actuated V-engine strategy. A low electrical signal must not automatically be interpreted as a credible closed-runner position.
Electrical range comes before functional interpretation
The source gives a position-sensor low boundary below 0.24 volts and a five-second electrical check. It separately lists stuck-open, stuck-closed and over-travel codes, which depend on comparing position behavior with the commanded state. Those functional conclusions require trustworthy feedback.
Ford enables IMRC monitoring after coolant exceeds 40°F. Record the operating state, full DTC set and bank 2 feedback rather than using an isolated low reading without its diagnostic context.
Do not substitute a control-solenoid specification
The same table includes the bank 2 IMRC control circuit, but its driver-status check is a different electrical function. The position-sensor voltage boundary is not a coil resistance or vacuum-actuator test specification.
Use the actual engine wiring information to identify the sensor signal, reference and return arrangement. The summary does not establish a universal physical bank location or determine whether the sensor, wiring or controller input caused the low state. Verification should show valid position feedback while the circuit monitor runs, followed by matching command/response behavior during functional events. P2021 alone does not justify replacing the complete intake manifold or treating the runner mechanism as mechanically stuck.
Source and applicability
This explanation covers the cited Ford monitor variants, not every vehicle displaying this code. Match the engine, sensor architecture and calibration before applying numerical limits.
Article source documents
Source checks describe how the text was prepared; they do not certify a diagnosis or confirm compatibility with every vehicle using this code.
Original code reference
Dictionary definition
Intake Manifold Runner Position Sensor/Switch Circuit Low Bank 2
This definition retains its original catalog scope. The article above is limited to its explicitly documented application.
Reference scope
Generic OBD-II definition.
A manufacturer label does not establish the model, year, engine or module to which a diagnosis applies. Read the safety and diagnostic limits.
Definition source
- DTC Database: pinned community code definitions
Source checked · MIT