Fuel and air

P00F1 — Intake Air Temperature Sensor 3 Circuit Erratic (Bank 2)

Severity: low Safe to drive

What P00F1 means

The engine control module detected that the signal from intake air temperature sensor 3 on bank 2 is jumping around or dropping out. The sensor is a thermistor whose resistance changes with temperature, and the ECM reads its voltage to estimate air temperature for fuel and timing adjustments. An unstable signal makes those calculations less accurate.

Symptoms

  • Check Engine light on
  • Worse fuel economy
  • Rough or unstable idle
  • Hesitation when accelerating
  • Problems that come and go, often with vibration or moisture

Possible causes

  1. Damaged or corroded wiring or connector in the sensor circuit
  2. Failed intake air temperature sensor 3
  3. Loose or poor terminal contact in the connector
  4. Chafed or broken harness near hot or moving parts
  5. ECM fault or software issue (rare)

How to diagnose

  1. Scan for codes and review freeze frame data, noting any other temperature or airflow sensor codes
  2. Watch live data for sensor 3 and compare it with other air temperature readings on a cold engine
  3. Inspect the connector and harness for corrosion, moisture, chafing and a loose fit
  4. Wiggle the harness and connector with the engine running and watch for signal spikes
  5. Measure sensor resistance and compare it with the spec at a known temperature
  6. Check reference voltage, ground and signal wire continuity back to the ECM
  7. Look for intake leaks or other issues that could disturb readings
  8. If wiring and sensor test good, check the ECM and for available software updates

Common fixes

  • Clean and repair connector terminals
  • Repair or replace the damaged section of wiring
  • Replace intake air temperature sensor 3
  • Update or replace the ECM if confirmed faulty

Questions and answers

What does P00F1 mean?

It means the circuit for intake air temperature sensor 3 on bank 2 is giving an intermittent or erratic signal. The ECM sees plausible readings mixed with impossible ones.

Can I drive with P00F1?

Usually yes for short trips. Fuel economy and smoothness may suffer, so get it checked soon.

How do I fix P00F1?

Start with the wiring and connector, then test the sensor. Replace the sensor only if testing shows it is bad.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.