WOMS
P code powertrain Medium severity

P0668 Intake Air Temperature Sensor 2 Circuit Range/Performance Problem

The OBD2 code P0668 indicates a problem with the range or performance of the Intake Air Temperature Sensor 2 circuit, suggesting that the sensor is providing readings that are outside the expected range or not...

Definition

The OBD2 code P0668 indicates a problem with the range or performance of the Intake Air Temperature Sensor 2 circuit, suggesting that the sensor is providing readings that are outside the expected range or not functioning correctly

Common causes

  • Faulty intake air temperature sensor 2
  • Wiring issues (shorts, opens, or corrosion)
  • Poor electrical connections
  • Faulty engine control module (ECM)
  • Intake air temperature sensor 2 circuit damage
  • Vacuum leaks
  • Contaminated sensor or connector
  • Incorrect sensor calibration or installation

Common misdiagnoses

  • Faulty Intake Air Temperature Sensor 1
  • Faulty Engine Coolant Temperature Sensor
  • Airflow Meter Issues
  • Vacuum Leaks
  • Faulty Engine Control Module (ECM)
  • Wiring or Connector Issues
  • Mass Air Flow Sensor Problems
  • Throttle Position Sensor Malfunction

Troubleshooting steps

  1. 1. Check for Additional Codes

    Use an OBD-II scanner to check for any other trouble codes that may be present. This can provide more context for the issue

  2. 2. Inspect the IAT Sensor

    Locate the Intake Air Temperature Sensor 2. Check for any physical damage, corrosion, or loose connections at the sensor and its wiring harness

  3. 3. Check Wiring and Connectors

    Inspect the wiring and connectors leading to the IAT sensor for any signs of wear, fraying, or damage. Ensure that all connections are secure and free of corrosion

  4. 4. Test the IAT Sensor

    Use a multimeter to test the resistance of the IAT sensor. Compare the readings to the specifications provided in the vehicle's service manual. If the readings are outside the specified range, the sensor may need to be replaced

  5. 5. Check for Air Leaks

    Inspect the intake system for any air leaks that could affect the readings of the IAT sensor. Look for cracks or loose fittings in the intake manifold, hoses, and air filter housing

  6. 6. Inspect the Engine Coolant Temperature (ECT) Sensor

    Sometimes, issues with the ECT sensor can affect the IAT sensor readings. Check the ECT sensor for proper operation and wiring

  7. 7. Check the Engine Control Module (ECM)

    If all other components are functioning correctly, there may be an issue with the ECM. Ensure that the ECM is receiving the correct signals from the IAT sensor

  8. 8. Clear the Codes and Test Drive

    After performing the checks and repairs, clear the trouble codes using the OBD-II scanner. Take the vehicle for a test drive to see if the code returns

  9. 9. Consult a Professional

    If the issue persists after performing these steps, it may be necessary to consult a professional mechanic or technician for further diagnosis. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the P0668 code