Intake Manifold Runner Position Sensor Circuit Low Bank 2
The P2021 code indicates that the Engine Control Module (ECM) has detected a low voltage signal from the intake manifold runner position sensor on bank 2. This sensor monitors the position of the intake manifold runner control (IMRC) flaps, which adjust airflow for optimal performance. A low circuit condition typically means the signal voltage is below the expected range, often due to a short to ground, faulty sensor, or wiring issues. This can cause poor engine performance, reduced fuel economy, and potential drivability problems.
01. Most Common Causes
- Faulty intake manifold runner position sensor
- Short to ground in sensor circuit
- Open or damaged wiring/connectors
- Corroded or loose electrical connections
- Failed ECM (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine power or hesitation
- Poor fuel economy
- Rough idle or stalling
- Possible engine misfire
03. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm code P2021 and check for related codes.
Step 2: Visually inspect the sensor and wiring for damage, corrosion, or loose connections.
Step 3: Test the sensor's voltage and ground circuits with a multimeter; compare to manufacturer specs.
Step 4: If sensor is faulty, replace it; if wiring issue, repair as needed.
Step 5: Clear codes and test drive to verify repair.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can cause reduced performance and potential engine damage. Short trips to a repair shop are acceptable.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for sensor replacement, plus diagnostic fees if done by a shop.